fix(clang-tidy): Enable clang-tidy else-after-return and redundant void checks

[Skylion007]

Description

• Clang-Tidy enable a few useful fixes:
• VirtualCalls (Check that Virtual Calls are not called in the constructor in the destructor ( they can be called if fully qualified, but they cannot be overridden during construction and destruction). This checks makes it very clear. Luckily, this behavior isn't used anywhere in the codebase, but this check will guard against it.
• Removes redundant void arguments.
• Most importantly removes all else-after-returns in the code base and prevents new code from introducing it. This is better style and a part of LLVM Style.

Suggested changelog entry:

* Add clang-tidy checks to further guard code style and remove all else after returns for better code readability. Also encourages following llvm-style (no ``else-after-returns``, proper usage of virtual functions in ctors and dtors).

[rwgk]

Awesome :-)

[rwgk]

Could you please also move the delete and return to separate lines while you're at it?
I had to squint at this for a while until I finally noticed the return h;

[Skylion007]

@rwgk Done.

[Skylion007]

Since I can't assign reviewers yet, ping @henryiii

[Skylion007]

ReOpen to retrigger

[rwgk]

@henryiii in the meantime I ran this through the Google-global testing: no issues.
Considering that you wrote "I like what I saw" and that this is a pure code health PR that's hardening our CI, I'll go ahead merging so we can move forward with other things.