Add minimum token permissions for all github workflow files (#870)

Co-authored-by: otelbot <[email protected]>

Author: opentelemetrybot

.github/workflows/elixir.yml

@@ -10,6 +10,9 @@ on:
     branches:
       - "main"
 
+permissions:
+  contents: read
+
 jobs:
   format:
     runs-on: ubuntu-24.04

.github/workflows/erlang.yml

@@ -12,10 +12,12 @@ on:
       - "main"
 
 permissions:
-  checks: write
+  contents: read
 
 jobs:
   build:
+    permissions:
+      checks: write
     name: Test on OTP ${{ matrix.otp_version }} and ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:

.github/workflows/labeler.yml

@@ -1,8 +1,13 @@
 name: "Pull Request Labeler"
 on: [pull_request_target]
 
+permissions:
+  contents: read
+
 jobs:
   triage:
+    permissions:
+      pull-requests: write # required for labeling PRs
     runs-on: ubuntu-24.04
     steps:
       - uses: actions/labeler@v4

.github/workflows/w3c_interop.yml

@@ -8,6 +8,9 @@ on:
     branches:
       - 'main'
 
+permissions:
+  contents: read
+
 jobs:
   interop_tests:
     name: Run W3C Trace Context Interop Tests