chore: update nightly tests container to version 8.1.0beta2 (#1018)

Author: melund

.github/workflows/nightly-tests.yml

@@ -67,7 +67,7 @@ jobs:
   test-linux:
     if: github.repository == 'anybody/ammr'
     runs-on: ubuntu-latest
-    container: ghcr.io/anybody/anybodycon-github-actions:8.0.5rc1
+    container: ghcr.io/anybody/anybodycon-github-actions:8.1.0beta2
     env:
       ANYBODY_SUPPRESS_DEPRECATION_MESSAGES: "Off"