Use goma-aware Fuchsia clang toolchain (#9430)

Update Fuchsia clang toolchain on Mac/Linux to goma-aware version,
tagged with `goma` in CIPD.

See:
https://chrome-infra-packages.appspot.com/p/fuchsia/clang/mac-amd64/+/goma
https://chrome-infra-packages.appspot.com/p/fuchsia/clang/linux-amd64/+/goma

DEPS

@@ -490,7 +490,7 @@ deps = {
      'packages': [
        {
         'package': 'fuchsia/clang/mac-amd64',
-        'version': 'BzmZEP9A83NSNSqnrff3k0tYJK7UXs0pknphn-quiZwC'
+        'version': 'Lc64-GTi4kihzkCnW8Vaa80TWTnMpZY0Fy6AqChmqvcC'
        }
      ],
      'condition': 'host_os == "mac"',
@@ -510,7 +510,7 @@ deps = {
      'packages': [
        {
         'package': 'fuchsia/clang/linux-amd64',
-        'version': 'dV3r0yk4WXi1C-QwjzNUA-pIkHCG3COYnrlt80GFacYC'
+        'version': 'oEsFSe99FkcDKVxZkAY0MKi6C-yYOan1m-QL45N33W8C'
        }
      ],
      'condition': 'host_os == "linux"',