Refactor[BMQ,MQB]: remove redundant virtual, s_allocator_p

[678098]

1. Remove s_allocator_p mentions from the code samples.
2. Put keyword final where it was missed.
3. Remove redundant virtual on methods that already marked as override.
   See also: https://learn.microsoft.com/en-us/cpp/code-quality/c26435?view=msvc-170
   https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#c128-virtual-functions-should-specify-exactly-one-of-virtual-override-or-final

[pniedzielski]

For the first patch, I have no strong opinions either way (with or without virtuals in the derived classes). But verified that these virtuals are redundant.

Second patch, 👍🏻 good changes

[bmq-oss-ci]

Build 399 of commit dc711ed has completed with FAILURE