Fixed broken build with a work around

- appending '(deprecated)' to an existing auto-slugified header ref
  broke the (naive) derivation algorithm, so an explicit slug ignoring
  the deprecated addition was set.
  That should be good style anyway, as a deprecation warning is an annotation and
  is normally reported on an error channel (not becoming part of an anchor or
  fragment identifier
- rendered the user facing single file markdown and self sustained html file

Signed-off-by: Stefan Hagen <stefan@hagen.link>

csaf_2.1/prose/edit/src/tests-02-optional.md

@@ -320,7 +320,7 @@ The relevant paths for this test are:
 
 > The hash algorithm `sha1` is used in one item of hashes without being accompanied by a second hash algorithm.
 
-### Missing TLP label (deprecated)
+### Missing TLP label (deprecated){#missing-tlp-label}
 
 It MUST be tested that `/document/distribution/tlp/label` is present and valid.