Release safety (#1096)

**Issue:**
Any branch can run critical release workflows without obtaining proper
approval.

**Description of changes:**
- Leveraging [GitHub
Environment](https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/using-environments-for-deployment)
to enforce safety of release workflows.
- The releases should now require approval from the
"aws-observability/aws-application-signals-team" member to run.

**Testing**:
Tested in this branch itself. The workflow blocks on approval.
Screenshot below.

![Screenshot 2025-06-06 at 8 51
08 AM](https://github.com/user-attachments/assets/88f55c4e-9613-4a28-9d02-4e22ff38f2e6)



By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache 2.0 license.

Author: srprash

.github/workflows/release-build.yml

@@ -21,6 +21,7 @@ permissions:
 
 jobs:
   build:
+    environment: Release
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4

.github/workflows/release-lambda.yml

@@ -21,6 +21,7 @@ permissions:
 
 jobs:
   build-layer:
+    environment: Release
     runs-on: ubuntu-latest
     outputs:
       aws_regions_json: ${{ steps.set-matrix.outputs.aws_regions_json }}

.github/workflows/release-udp-exporter.yml

@@ -21,6 +21,7 @@ jobs:
       id-token: write
 
   release-udp-exporter:
+    environment: Release
     runs-on: ubuntu-latest
     needs: validate-udp-exporter-e2e-test
     steps: