ci: add GitHub token permissions for workflows (#479)

Signed-off-by: Varun Sharma <[email protected]>

Author: varunsh-coder

.github/workflows/browsers.yml

@@ -2,6 +2,9 @@ name: Browsers
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Browsers

.github/workflows/bundlers.yml

@@ -2,6 +2,9 @@ name: Bundlers
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Bundlers

.github/workflows/node.yml

@@ -2,6 +2,9 @@ name: Node.js
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Node.js