Fix tests that are "hard coded" to expect x86_64 output by mocking the platform interface.

Submitted upstream:
https://github.com/pypa/packaging/pull/176

diff --git a/tests/test_tags.py b/tests/test_tags.py
index 1eacf68..0a3f1b4 100644
--- a/tests/test_tags.py
+++ b/tests/test_tags.py
@@ -435,37 +435,43 @@ class TestManylinuxPlatform:
         linux_platform = list(tags._linux_platforms(is_32bit=False))
         assert linux_platform == ["linux_x86_64"]
 
-    def test_linux_platforms_manylinux1(self, monkeypatch):
+    def test_linux_platforms_manylinux1(self, is_x86, monkeypatch):
         monkeypatch.setattr(
             tags, "_is_manylinux_compatible", lambda name, _: name == "manylinux1"
         )
-        if platform.system() != "Linux":
+        if platform.system() != "Linux" or not is_x86:
             monkeypatch.setattr(distutils.util, "get_platform", lambda: "linux_x86_64")
+            monkeypatch.setattr(platform, "machine", lambda: "x86_64")
         platforms = list(tags._linux_platforms(is_32bit=False))
-        assert platforms == ["manylinux1_x86_64", "linux_x86_64"]
+        arch = platform.machine()
+        assert platforms == ["manylinux1_" + arch, "linux_" + arch]
 
-    def test_linux_platforms_manylinux2010(self, monkeypatch):
+    def test_linux_platforms_manylinux2010(self, is_x86, monkeypatch):
         monkeypatch.setattr(
             tags, "_is_manylinux_compatible", lambda name, _: name == "manylinux2010"
         )
-        if platform.system() != "Linux":
+        if platform.system() != "Linux" or not is_x86:
             monkeypatch.setattr(distutils.util, "get_platform", lambda: "linux_x86_64")
+            monkeypatch.setattr(platform, "machine", lambda: "x86_64")
         platforms = list(tags._linux_platforms(is_32bit=False))
-        expected = ["manylinux2010_x86_64", "manylinux1_x86_64", "linux_x86_64"]
+        arch = platform.machine()
+        expected = ["manylinux2010_" + arch, "manylinux1_" + arch, "linux_" + arch]
         assert platforms == expected
 
-    def test_linux_platforms_manylinux2014(self, monkeypatch):
+    def test_linux_platforms_manylinux2014(self, is_x86, monkeypatch):
         monkeypatch.setattr(
             tags, "_is_manylinux_compatible", lambda name, _: name == "manylinux2014"
         )
-        if platform.system() != "Linux":
+        if platform.system() != "Linux" or not is_x86:
             monkeypatch.setattr(distutils.util, "get_platform", lambda: "linux_x86_64")
+            monkeypatch.setattr(platform, "machine", lambda: "x86_64")
         platforms = list(tags._linux_platforms(is_32bit=False))
+        arch = platform.machine()
         expected = [
-            "manylinux2014_x86_64",
-            "manylinux2010_x86_64",
-            "manylinux1_x86_64",
-            "linux_x86_64",
+            "manylinux2014_" + arch,
+            "manylinux2010_" + arch,
+            "manylinux1_" + arch,
+            "linux_" + arch,
         ]
         assert platforms == expected
 
ef='/guix/commit/gnu/packages/vulkan.scm?id=75b775e81b5a81a59656eeba8811b42f45d503da'>Merge branch 'staging'</a></td><td>Leo Famulari</td></tr>
<tr><td><span title='2021-01-29 12:46:19 +0100'>2021-01-29</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=cd1ed8801ac332607f69a4481f49580ccb926c60'>gnu: vkd3d: Update to 1.2.</a><span class='msg-avail'>...</span></td><td>Leo Prikler</td></tr>
<tr><td><span title='2020-12-13 21:44:12 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=8f8185b996036be7100b3016f27accec76ccd094'>gnu: shaderc: Update to 2020.4.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-12-13 21:44:12 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=9045b3bb34a9514d0e6dc122e7b5d9be8c29cd32'>gnu: vulkan-tools: Update to 1.2.162.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-12-13 21:44:12 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=85ab862a7da2a7f9d04fbd96e5a6d249d02ef14a'>gnu: vulkan-loader: Update to 1.2.162.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-12-13 21:44:11 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=3a72e26be334e80868bb4e88a9a99704fb17fe52'>gnu: vulkan-headers: Update to 1.2.164.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-12-13 21:44:11 +0100'>2020-12-13</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=f34060199aecbee50538fb356124ff5a87120558'>gnu: glslang: Update to 10-11.0.0.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2020-07-25 16:16:08 +0200'>2020-07-25</span></td><td><a href='/guix/commit/gnu/packages/vulkan.scm?id=05cf7180be85981228ff9d2eefddf6343fe37237'>gnu: vulkan-tools: Update to 1.2.148.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>