Bump runtime from 3.1-1 to 3.1-3 (#189)

Bumps runtime from 3.1-1 to 3.1-3.

---
updated-dependencies:
- dependency-name: runtime
  dependency-version: 3.1-3
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Dockerfile

@@ -1 +1 @@
-FROM astrocrpublic.azurecr.io/runtime:3.1-1
+FROM astrocrpublic.azurecr.io/runtime:3.1-3