Exclude Microsoft.Extensions.Caching.Memory from Dependabot

Author: bkoelman

.github/dependabot.yml

@@ -22,3 +22,5 @@ updates:
       # Block major updates of packages that require a matching .NET version.
       - dependency-name: "Microsoft.AspNetCore*"
         update-types: ["version-update:semver-major"]
+      - dependency-name: "Microsoft.Extensions*"
+        update-types: ["version-update:semver-major"]