test: remove test-path-parse-6229.js from known issues

This test precedented the official documentation that states that
this is an expected behavior.

PR-URL: https://github.com/nodejs/node/pull/26913
Refs: https://github.com/nodejs/node/issues/6229
Refs: https://github.com/nodejs/node/pull/12181


Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Signed-off-by: Beth Griggs <Bethany.Griggs@uk.ibm.com>