build(bazel): update workspace file to work with protobuf v29 (#14864)

Author: scotthart

bazel/workspace0.bzl

@@ -71,10 +71,21 @@ def gl_cpp_workspace0(name = None):
         http_archive,
         name = "rules_cc",
         urls = [
-            "https://github.com/bazelbuild/rules_cc/releases/download/0.0.9/rules_cc-0.0.9.tar.gz",
+            "https://github.com/bazelbuild/rules_cc/releases/download/0.0.15/rules_cc-0.0.15.tar.gz",
+        ],
+        sha256 = "f4aadd8387f381033a9ad0500443a52a0cea5f8ad1ede4369d3c614eb7b2682e",
+        strip_prefix = "rules_cc-0.0.15",
+    )
+
+    # protobuf requires this
+    maybe(
+        http_archive,
+        name = "bazel_skylib",
+        sha256 = "d00f1389ee20b60018e92644e0948e16e350a7707219e7a390fb0a99b6ec9262",
+        urls = [
+            "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.7.0/bazel-skylib-1.7.0.tar.gz",
+            "https://github.com/bazelbuild/bazel-skylib/releases/download/1.7.0/bazel-skylib-1.7.0.tar.gz",
         ],
-        sha256 = "2037875b9a4456dce4a79d112a8ae885bbc4aad968e6587dca6e64f3a0900cdf",
-        strip_prefix = "rules_cc-0.0.9",
     )
 
     # The version of `rules_apple` loaded by gRPC is too old for Bazel 7.