Deprecate `AllocatorMemoryStrategy` and remove related test cases

[fujitatomoya]

follow up of #2988

AllocatorMemoryStrategy and related code is "dead code" that was part of the old executor (StaticSingleThreadedExecutor in the last) implementation before the double buffering changes introduced shortly before Jazzy.
We need to deprecate AllocatorMemoryStrategy and remove related test files and scenarios all together. Deprecation period requires one distro release, that said deprecation warning stays in Lyrical Luth, and on turtle-M we can remove AllocatorMemoryStrategy.

with quick code scan, i see the following needs to be done.

• deprecate AllocatorMemoryStrategy<Alloc> and MemoryStrategy (base class) including all methods.
• test_allocator_memory_strategy.cpp, test_memory_strategy.cpp can be removed.
• Executor options should be adjusted with this deprecation.
• External packages using custom allocators? (realtime_support, demos)

could be more.

[Scott-Duncan]

Hello! I’m new to contributing to ROS2, and I’d like to work on this issue if that is okay