allow uploads of wheels targeting macOS 26 (#19018)

Co-authored-by: Dustin Ingram <[email protected]>

Author: btucker

tests/unit/forklift/test_legacy.py

@@ -2844,6 +2844,7 @@ def test_upload_attestation_fails_without_oidc_publisher(
             "macosx_11_0_x86_64",
             "macosx_10_15_arm64",
             "macosx_11_10_universal2",
+            "macosx_26_0_arm64",
             "ios_13_0_arm64_iphoneos",
             "ios_13_0_arm64_iphonesimulator",
             "ios_13_0_x86_64_iphonesimulator",
@@ -3410,6 +3411,7 @@ def test_upload_fails_with_invalid_filename(
             "macosx_9_2_x86_64",
             "macosx_16_2_arm64",
             "macosx_10_15_amd64",
+            "macosx_27_0_arm64",
         ],
     )
     def test_upload_fails_with_unsupported_wheel_plat(

warehouse/forklift/legacy.py

@@ -140,6 +140,7 @@
     "13",
     "14",
     "15",
+    "26",
 }
 
 _ios_platform_re = re.compile(