Add permissions to GitHub Actions workflows (#1344)

Explicitly set required permissions in test-conda.yml and test-package-build.yml workflows to improve security and clarify access needs.

Author: edeno

.github/workflows/test-conda.yml

@@ -1,4 +1,6 @@
 name: Tests
+permissions:
+  contents: read
 
 on:
   push:

.github/workflows/test-package-build.yml

@@ -1,4 +1,8 @@
 name: Test package building
+permissions:
+  contents: read
+  pull-requests: write
+  id-token: write
 
 on:
   push: