Update pr-custom-review.yml 3 Core-devs to approve (#7453)

polkadot/.github/pr-custom-review.yml

@@ -23,7 +23,7 @@ rules:
       include: .*
       # excluding files from 'Runtime files' and 'CI files' rules
       exclude: ^runtime/(kusama|polkadot)/src/[^/]+\.rs$|^\.gitlab-ci\.yml|^(?!.*\.dic$|.*spellcheck\.toml$)scripts/ci/.*|^\.github/.*
-    min_approvals: 2
+    min_approvals: 3
     teams:
       - core-devs