Substitute a11r for ctiller in all OWNERS files
diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index cb32281..093e939 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -1,7 +1,7 @@
# Auto-generated by the tools/mkowners/mkowners.py tool
# Uses OWNERS files in different modules throughout the
# repository as the source of truth for module ownership.
-/**/OWNERS @markdroth @nicolasnoble @ctiller
-/bazel/** @nicolasnoble @dgquintas @ctiller
-/src/core/ext/filters/client_channel/** @markdroth @dgquintas @ctiller
+/**/OWNERS @markdroth @nicolasnoble @a11r
+/bazel/** @nicolasnoble @dgquintas @a11r
+/src/core/ext/filters/client_channel/** @markdroth @dgquintas @a11r
/tools/run_tests/performance/** @ncteisen @matt-kwong @ctiller