build(bazel): use platform to detect windows

Author: gjasny

BUILD.bazel

@@ -1,11 +1 @@
 package(default_visibility = ["//visibility:public"])
-
-config_setting(
-    name = "windows",
-    values = {"cpu": "x64_windows"},
-)
-
-config_setting(
-    name = "windows_msvc",
-    values = {"cpu": "x64_windows_msvc"},
-)

push/BUILD.bazel

@@ -16,8 +16,7 @@ cc_library(
         ["include/**/*.h"],
     ) + [":export_header"],
     linkopts = select({
-        "//:windows": [],
-        "//:windows_msvc": [],
+        "@platforms//os:windows": [],
         "//conditions:default": ["-lpthread"],
     }),
     strip_include_prefix = "include",