github: enable github actions for postsubmit testing

This gives us a bit of feedback by running our testsuite on Linux,
macOS, and Windows platforms.   While Linux & macOS are passing,
Windows fails some of them.  We can figure that out later.  This
is better than what we have now which is manual one-offs.

Change-Id: I9d2d644be97ec76645db0bc15739e7679310a647
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/255314
Reviewed-by: David Pursehouse <dpursehouse@collab.net>
Tested-by: Mike Frysinger <vapier@google.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/README.md b/README.md
index 1e3c46ce..3989dde1 100644
--- a/README.md
+++ b/README.md
@@ -15,6 +15,8 @@ that you can put anywhere in your path.
 * [repo Hooks](./docs/repo-hooks.md)
 * [Submitting patches](./SUBMITTING_PATCHES.md)
 * Running Repo in [Microsoft Windows](./docs/windows.md)
+* GitHub mirror: <https://github.com/GerritCodeReview/git-repo>
+* Postsubmit tests: <https://github.com/GerritCodeReview/git-repo/actions>
 
 ## Install