[Internal] Automatically trigger integration tests on PR (#369)

## Changes
Automatically trigger integration tests when a PR is opened or updated

## Tests
Workflow below.

.github/workflows/integration-tests.yml

@@ -0,0 +1,57 @@
+name: Integration Tests
+
+on:
+    pull_request:
+        types: [opened, synchronize]
+
+    merge_group:
+
+jobs:
+    trigger-tests:
+        if: github.event_name == 'pull_request'
+        name: Trigger Tests
+        runs-on: ubuntu-latest
+        environment: "test-trigger-is"
+
+        steps:
+            - uses: actions/checkout@v3
+
+            - name: Generate GitHub App Token
+              id: generate-token
+              uses: actions/create-github-app-token@v1
+              with:
+                  app-id: ${{ secrets.DECO_WORKFLOW_TRIGGER_APP_ID }}
+                  private-key: ${{ secrets.DECO_WORKFLOW_TRIGGER_PRIVATE_KEY }}
+                  owner: ${{ secrets.ORG_NAME }}
+                  repositories: ${{secrets.REPO_NAME}}
+
+            - name: Trigger Workflow in Another Repo
+              env:
+                  GH_TOKEN: ${{ steps.generate-token.outputs.token }}
+              run: |
+                  gh workflow run sdk-java-isolated-pr.yml -R ${{ secrets.ORG_NAME }}/${{secrets.REPO_NAME}} \
+                  --ref main \
+                  -f pull_request_number=${{ github.event.pull_request.number }} \
+                  -f commit_sha=${{ github.event.pull_request.head.sha }}
+
+    # Statuses and checks apply to specific commits (by hash).
+    # Enforcement of required checks is done both at the PR level and the merge queue level.
+    # In case of multiple commits in a single PR, the hash of the squashed commit
+    # will not match the one for the latest (approved) commit in the PR.
+    # We auto approve the check for the merge queue for two reasons:
+    # * Queue times out due to duration of tests.
+    # * Avoid running integration tests twice, since it was already run at the tip of the branch before squashing.
+    auto-approve:
+        if: github.event_name == 'merge_group'
+        runs-on: ubuntu-latest
+        steps:
+            - name: Mark Check
+              env:
+                  GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+              shell: bash
+              run: |
+                  gh api -X POST -H "Accept: application/vnd.github+json" \
+                    -H "X-GitHub-Api-Version: 2022-11-28" \
+                    /repos/${{ github.repository }}/statuses/${{ github.sha }} \
+                    -f 'state=success' \
+                    -f 'context=Integration Tests Check'