[rbe] Point to Fuchsia mirror of remote-apis-sdks

Bug: b/274014314
Change-Id: I14435b234ba5e64afe07782aa5460bece4d1cde7
Reviewed-on: https://fuchsia-review.googlesource.com/c/infra/3pp/+/827256
Reviewed-by: Marc-Antoine Ruel <maruel@google.com>
Commit-Queue: David Fang <fangism@google.com>
diff --git a/remote-apis-sdks/fetch.sh b/remote-apis-sdks/fetch.sh
index 13f56b3..bd0e170 100755
--- a/remote-apis-sdks/fetch.sh
+++ b/remote-apis-sdks/fetch.sh
@@ -13,7 +13,7 @@
 EOF
 }
 
-readonly _REPO="https://github.com/bazelbuild/remote-apis-sdks"
+readonly _REPO="https://fuchsia.googlesource.com/third_party/github.com/bazelbuild/remote-apis-sdks"
 
 # There are no release or tags.
 # Manually bump these as needed: