Fix path for Chrome DevTools external plugin (#1784)

* Fixing path on chrome devtools external pluginPath is to the folder in the repo where the plugin structure starts, not where the plugin.json file lives.

* Updating validation scripts and guidance to avoid this mistake again

.github/ISSUE_TEMPLATE/external-plugin.yml

@@ -44,8 +44,8 @@ body:
     id: plugin-path
     attributes:
       label: Plugin path inside the repository
-      description: Optional if the plugin lives at the repository root.
-      placeholder: .github/plugins/my-plugin
+      description: Optional if the plugin lives at the repository root. Otherwise, enter the folder where the plugin structure starts, not the plugin.json file.
+      placeholder: plugins/my-plugin
     validations:
       required: false
   - type: input

.github/plugin/marketplace.json

@@ -126,7 +126,6 @@
       "source": {
         "source": "github",
         "repo": "ChromeDevTools/chrome-devtools-mcp",
-        "path": ".github/plugin/plugin.json",
         "ref": "chrome-devtools-mcp-v1.0.1"
       }
     },