add repo/cody to labeler (#5937)

RELATED TO sourcegraph/jetbrains#2472

Adding `repo/cody` to help distinguish where issues originate from when
we sync them back into linear


## Test plan
N/A
<!-- Required. See
https://docs-legacy.sourcegraph.com/dev/background-information/testing_principles.
-->

## Changelog

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https://www.notion.so/sourcegraph/Writing-a-changelog-entry-dd997f411d524caabf0d8d38a24a878c
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.github/labeler.yml

@@ -1,2 +1,4 @@
 bug:
     - '(bug:)'
+repo/cody:
+    - '/.*/'