GH-103484: Fix broken links reported by linkcheck (#103608)

* Doc: Fix broken links reported by linkcheck

* Apply suggestions from code review

- Remove extra diff line in faq/library.rst (merwok)
- Use HTTPS to link Unicode 15.0.0 to solve a redirect (hugovk)
- Use wayback machine link for openssl 1.1.0 instead of linking 1.1.1, "as this text mentions a feature from 1.1.0" (hugovk)

Co-authored-by: Éric <merwok@netwok.org>
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>

* Doc: Make mark-up code as literal

* Doc: Alphabetize items in linkcheck_ignore

Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>

* Doc: Improve comment in sphinx conf

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>

---------

Co-authored-by: Éric <merwok@netwok.org>
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>

Doc/conf.py

@@ -263,6 +263,24 @@ linkcheck_allowed_redirects = {
     r'https://github.com/python/cpython/tree/.*': 'https://github.com/python/cpython/blob/.*'
 }
 
+linkcheck_anchors_ignore = [
+    # ignore anchors that start with a '/', e.g. Wikipedia media files:
+    # https://en.wikipedia.org/wiki/Walrus#/media/File:Pacific_Walrus_-_Bull_(8247646168).jpg
+    r'\/.*',
+]
+
+linkcheck_ignore = [
+    # The crawler gets "Anchor not found"
+    r'https://developer.apple.com/documentation/.+?#.*',
+    r'https://devguide.python.org.+?/#.*',
+    r'https://github.com.+?#.*',
+    # Robot crawlers not allowed: "403 Client Error: Forbidden"
+    r'https://support.enthought.com/hc/.*',
+    # SSLError CertificateError, even though it is valid
+    r'https://unix.org/version2/whatsnew/lp64_wp.html',
+]
+
+
 # Options for extensions
 # ----------------------