Add an entry for "github.com/googleapis/gax-go/v2" to default_gazelle…

…_overrides.bzl

When updating to v0.32.0 anyone with a transient dependency on `github.com/googleapis/gax-go/v2` will need to add an override `gazelle:proto disable` directive. See here for discussion: bazel-contrib/rules_go#3625 (comment)

Adding the directive as a default should prevent a bunch of manual effort.

internal/bzlmod/default_gazelle_overrides.bzl

@@ -23,6 +23,9 @@ DEFAULT_DIRECTIVES_BY_PATH = {
         "gazelle:build_file_name BUILD.bazel",
         "gazelle:build_file_proto_mode disable_global",
     ],
+    "github.com/googleapis/gax-go/v2": [
+        "gazelle:proto disable",
+    ],
     "github.com/googleapis/gnostic": [
         "gazelle:proto disable",
     ],