Harden iOS CI retries for runner and gem flakes

Summary:
Two unrelated iOS CI jobs failed on `main` commit `cd2de187e8878119896159371225acbb9dfa5d9c`. The commit itself only changed Android autolinking code, so neither failure was attributable to its product change. This patch hardens the two affected CI paths without weakening their final failure semantics.

### Dynamic-framework Bundler setup

Failed job: https://github.com/react/react-native/actions/runs/36918732275/job/110559233737

The Debug dynamic-framework job failed while `ruby/setup-ruby` was performing its implicit one-shot Bundler installation. Its Release sibling passed in the same workflow, and both lanes passed on the immediately preceding `main` commit. That evidence points to a transient RubyGems/Bundler setup failure rather than a deterministic React Native regression.

Disable the implicit installation with `bundler: none`, read the exact pinned Bundler version from `Gemfile.lock`, and install it with three bounded attempts and 10-/20-second backoff. The script fails immediately if the lockfile version cannot be determined, and persistent installation failures remain red after the third attempt.

### E2E hosted-runner loss

Failed job: https://github.com/react/react-native/actions/runs/36918732275/job/110577294552

The Release E2E matrix cell lost communication with its GitHub-hosted runner before reaching the step that writes its explicit status output. The downstream report job checked only that output. Because runner loss left the output empty rather than setting it to `failure`, the report job incorrectly emitted success and skipped the existing fresh-runner retry chain.

Also inspect `needs.test.result`. Any non-successful matrix result now propagates failure and activates the existing retry jobs, while successful jobs and explicit test failures retain their previous behaviour. This changes failure reporting only; it does not alter E2E test execution.

Changelog: [Internal]

Differential Revision: D122967026

Author: cortinico

.github/actions/test-ios-rntester/action.yml

@@ -41,6 +41,27 @@ runs:
       uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ inputs.ruby-version }}
+        bundler: none
+    - name: Install Bundler
+      shell: bash
+      run: |
+        BUNDLER_VERSION="$(awk '/BUNDLED WITH/{getline; print $1}' Gemfile.lock)"
+        if [ -z "$BUNDLER_VERSION" ]; then
+          echo "Could not determine Bundler version from Gemfile.lock." >&2
+          exit 1
+        fi
+        for attempt in 1 2 3; do
+          echo "Attempt $attempt of 3"
+          if gem install bundler --version "$BUNDLER_VERSION" --no-document; then
+            exit 0
+          fi
+          if [ "$attempt" -lt 3 ]; then
+            echo "Attempt $attempt failed. Retrying..."
+            sleep "$((attempt * 10))"
+          fi
+        done
+        echo "All 3 attempts failed."
+        exit 1
     - name: Set Hermes prebuilt version
       shell: bash
       run: |

.github/workflows/e2e-ios-rntester.yml

@@ -60,7 +60,8 @@ jobs:
     steps:
       - id: check
         run: |
-          if [[ "${{ needs.test.outputs.status }}" == "failure" ]]; then
+          if [[ "${{ needs.test.result }}" != "success" ||
+                "${{ needs.test.outputs.status }}" == "failure" ]]; then
             echo "status=failure" >> $GITHUB_OUTPUT
           else
             echo "status=success" >> $GITHUB_OUTPUT