docs: update metadata.yml where token isn't needed

source/plugins/community/screenshot/README.md

@@ -91,7 +91,7 @@ name: XKCD of the day
 uses: lowlighter/metrics@latest
 with:
   filename: metrics.plugin.screenshot.svg
-  token: ${{ secrets.METRICS_TOKEN }}
+  token: NOT_NEEDED
   base: ""
   plugin_screenshot: yes
   plugin_screenshot_title: XKCD of the day

source/plugins/community/screenshot/examples.yml

@@ -2,7 +2,7 @@
   uses: lowlighter/metrics@latest
   with:
     filename: metrics.plugin.screenshot.svg
-    token: ${{ secrets.METRICS_TOKEN }}
+    token: NOT_NEEDED
     base: ""
     plugin_screenshot: yes
     plugin_screenshot_title: XKCD of the day