fix: add read permissions to workflow YAML files

Author: fukusuket

.github/workflows/integration-test.yml

@@ -1,5 +1,8 @@
 name: Integration Test
 
+permissions:
+  contents: read
+
 on:
   workflow_dispatch:
 

.github/workflows/release.yml

@@ -1,5 +1,8 @@
 name: Hayabusa Release Automation
 
+permissions:
+  contents: read
+
 on:
   workflow_dispatch:
     inputs:

.github/workflows/rust.yml

@@ -1,5 +1,8 @@
 name: Rust
 
+permissions:
+  contents: read
+
 on:
   pull_request:
     branches:

.github/workflows/timeline-diff.yml

@@ -1,5 +1,8 @@
 name: Check CSV timeline and JSON timeline Diff
 
+permissions:
+  contents: read
+
 on:
   workflow_dispatch: