chore(ci): add ci-success step so we can make this a condition for merging (#316)

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## Motivation

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Adds `ci-success` similar to how we have in Foundry already

## Solution

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A PR will follow to further harden the workflow

Author: zerosnacks

.github/workflows/ci.yml

@@ -109,3 +109,21 @@ jobs:
 
   deny:
     uses: ithacaxyz/ci/.github/workflows/deny.yml@main
+
+  ci-success:
+    runs-on: ubuntu-latest
+    if: always()
+    needs:
+      - test
+      - doctest
+      - feature-checks
+      - clippy
+      - docs
+      - fmt
+      - deny
+    timeout-minutes: 30
+    steps:
+      - name: Decide whether the needed jobs succeeded or failed
+        uses: re-actors/alls-green@release/v1
+        with:
+          jobs: ${{ toJSON(needs) }}