[gcc(refs/vendors/microsoft/heads/main)] Set up mirroring for gcc-11 branch.

[Eugene Rozenfeld]

https://gcc.gnu.org/g:b0ec6ca334d33acae83a4d639381a3c134db1f7f

commit b0ec6ca334d33acae83a4d639381a3c134db1f7f
Author: Eugene Rozenfeld <erozen@microsoft.com>
Date:   Wed Jul 27 17:34:28 2022 -0700

    Set up mirroring for gcc-11 branch.

Diff:
---
 .github/workflows/update-mirror-branches.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.github/workflows/update-mirror-branches.yaml b/.github/workflows/update-mirror-branches.yaml
index 24f299a6704..7beb047cc8a 100644
--- a/.github/workflows/update-mirror-branches.yaml
+++ b/.github/workflows/update-mirror-branches.yaml
@@ -46,6 +46,8 @@ jobs:
             githubBranch: current
           - upstreamBranch: '9.1.0'
             githubBranch: gcc-9.1.0
+          - upstreamBranch: 'releases/gcc-11'
+            githubBranch: 'releases/gcc-11'
 
         # Exclude the default case because we can't have empty matricies
         exclude: