Release v1.2.3.2 (#3546)
Release v1.2.3.2 (#3546)

Changelog:
- Run PTF tests under different kernel versions (3535) [Jan Palimąka]
- add set_member_id in action list for action selector (3540) [Usha Gupta]
- Dpdk backend: Flatten header union into individual fields (3524) [Usha Gupta]
- Set C++ standard only if it is not set at parent scope (3541) [Vladimír Štill]
- Fixing bug in ParserUnroll for infinite loops without header stacks  (3538) [VolodymyrPeschanenkoLitSoft]
- remove unused lib/alloc.h [Chris Dodd]
- Constant-fold static_assert calls (3533) [Mihai Budiu]
- Dpdk Backend: Update default timeout values for learner table entries (3530) [Usha Gupta]
- Since dpdk now Support large struct fields(more than 64 bits) as key (3528) [Kamlesh Kumar]
- Fix hdr align (3521) [Kamlesh Kumar]
- Forbid use of .lastIndex outside of parsers (3523) [Mihai Budiu]
- Fixing bug in parserUnroll (3503) [VolodymyrPeschanenkoLitSoft]
- Fix: prevent copy elimination for statement which does not support constant values (3512) [Kamlesh Kumar]
- Fixes related to type and function specialization (3458) [Mihai Budiu]
- Prototype implementation of static_assert (3196) [Mihai Budiu]
- Silence -Warray-bounds for generated code for protobuf (3515) [Dávid Bolvanský]
- cmake: Fixed multi line comment (3513) [Dávid Bolvanský]
- Add new option to build p4c with LTO (3470) [Dávid Bolvanský]
- Load table action from json without 'name' field for BMV2 (3435) [VolodymyrPeschanenkoIntel]
- Add null check for default action property (3500) [Usha Gupta]

Co-authored-by: rst0git <1fc74c852e564fe1b2309c83ad32210212547dda@users.noreply.github.com>
p4lang/p4c,p4lang/p4c,p4lang/p4c,p4lang/p4c,p4lang/p4c