help: Clean up settings_html and subscriptions_html.

After some thinking, I don't think there's any actual value to doing
the ../ style relative links here, whereas there is actual harm from
the links being slightly broken in the current model.  We fix this by
just using /#settings as the URL.

Fixes #8978.

tools/documentation_crawler/documentation_crawler/spiders/check_help_documentation.py

@@ -44,9 +44,7 @@ class HelpDocumentationSpider(UnusedImagesLinterSpider):
     name = "help_documentation_crawler"
     start_urls = ['http://localhost:9981/help']
     deny_domains = []  # type: List[str]
-    deny = ['/privacy',
-            # Ignored because scrapy seems to not process relatively URLs with ../ properly.
-            '[.][.]/']
+    deny = ['/privacy']
     images_path = "static/images/help"