fix bugs with nested column jsonpath parser

[clintropolis]

Description

Fixes some bugs with the custom jsonpath parser used by nested columns. It was overly restrictive in where ' could appear, which prevented extracting properties from json that contain single quotes, as well as fixes some issues with the 'normalized' jsonpath generated from parsed path parts.

This PR has:

• been self-reviewed.
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• been tested in a test Druid cluster.

[imply-cheddar]

I don't see new tests added, only changing of old tests. Was the bad behavior actually captured and encoded in those tests such that changing them is now verifying good behavior? Is there really no new thing that we can add to also test the bug fix here?

[clintropolis]

I don't see new tests added, only changing of old tests. Was the bad behavior actually captured and encoded in those tests such that changing them is now verifying good behavior? Is there really no new thing that we can add to also test the bug fix here?

The "new" test is https://github.com/apache/druid/pull/12831/files#diff-886d639244f5abe97ecb6fcfed49b7f6baaa041b10d843982e82984c9f5653a4R316 which was just added another case to a test that tests a variety of paths. The case immediately before it was a case of the incorrect path being "expected" and so fixed.