The plugin loader can now determine the Qt version and find the appropriate
directory.
Refs #20288

Refs #20288

Searching code required them ordered by Z then A.
Refs #0

Re #20790

Re #20790

This reverts commit c171e71b.

Re #20790

Re #20790

Re #20790

Refs #20837

This uses the -fix option on clang-tidy to automatically fix all
the cases where we make an extra copy while looping.

This uses the -fix option on clang-tidy to automatically fix all
the cases not using bool literals that have crept into Mantid.

This uses the -fix option on clang-tidy to automatically fix all
the unused usings declarations that have crept into Mantid.