Remove comments about npm cache

Author: henrymercer

.github/actions/release-initialise/action.yml

@@ -19,7 +19,7 @@ runs:
       uses: actions/setup-node@v6
       with:
         node-version: 24
-        cache: 'npm' # shared with the "Rebuild Action" workflow
+        cache: 'npm'
 
     - name: Set up Python
       uses: actions/setup-python@v6

.github/workflows/post-release-mergeback.yml

@@ -50,7 +50,7 @@ jobs:
       - uses: actions/setup-node@v6
         with:
           node-version: 24
-          cache: 'npm' # shared with the "Rebuild Action" workflow
+          cache: 'npm'
       - uses: actions/setup-python@v6
         with:
           python-version: '3.12'