Fix/issue 103

[italovalcy]

Closes #103

Summary

See updated changelog file and/or add any other summarized helpful information for reviewers

Local Tests

With the proposed change, we only fix the get_size fo ActionHeader objs, the children objs will keep their size with multiple of 8:

> python3
Python 3.13.2 (main, Feb  4 2025, 14:51:09) [Clang 16.0.0 (clang-1600.0.26.6)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from pyof.v0x04.common.action import ActionExperimenter, ActionGroup, ActionHeader, ActionCopyTTLIn, ActionCopyTTLOut, ActionDecMPLSTTL, ActionSetMPLSTTL, ActionDecNWTTL, ActionSetNWTTL, ActionOutput, ActionPopMPLS, ActionPopPBB, ActionPopVLAN, Ac\
tionPush, ActionSetField, ActionSetQueue, ActionType, ActionHeader
>>> accs_ids = [ActionOutput(port=0), ActionCopyTTLOut(), ActionCopyTTLIn(), ActionSetMPLSTTL(mpls_ttl=0), ActionDecMPLSTTL(), ActionPush(action_type=ActionType.OFPAT_PUSH_VLAN, ethertype=0), ActionPopVLAN(), ActionPush(action_type=ActionType.OFPAT_PU\
SH_MPLS, ethertype=0), ActionPopMPLS(ethertype=0), ActionSetQueue(queue_id=0), ActionGroup(group_id=0), ActionSetNWTTL(nw_ttl=0), ActionDecNWTTL(), ActionPush(action_type=ActionType.OFPAT_PUSH_PBB, ethertype=0), ActionPopPBB(), ActionExperimenter(leng\
th=0, experimenter=0)]
>>>
>>> for acc in accs_ids:
...     print(acc.get_size(), acc)
...
16 ActionOutput(port=0)
8 <pyof.v0x04.common.action.ActionCopyTTLOut object at 0x10bc05400>
8 <pyof.v0x04.common.action.ActionCopyTTLIn object at 0x10bc05010>
8 <pyof.v0x04.common.action.ActionSetMPLSTTL object at 0x10bc052b0>
8 <pyof.v0x04.common.action.ActionDecMPLSTTL object at 0x10bc06cf0>
8 <pyof.v0x04.common.action.ActionPush object at 0x10bc06e40>
8 <pyof.v0x04.common.action.ActionPopVLAN object at 0x10bc06f90>
8 <pyof.v0x04.common.action.ActionPush object at 0x10bc956d0>
8 <pyof.v0x04.common.action.ActionPopMPLS object at 0x10bc070e0>
8 <pyof.v0x04.common.action.ActionSetQueue object at 0x10bc07230>
8 <pyof.v0x04.common.action.ActionGroup object at 0x10bc07380>
8 <pyof.v0x04.common.action.ActionSetNWTTL object at 0x10bc074d0>
8 <pyof.v0x04.common.action.ActionDecNWTTL object at 0x10bc07620>
8 <pyof.v0x04.common.action.ActionPush object at 0x10bc95950>
8 <pyof.v0x04.common.action.ActionPopPBB object at 0x10bc07770>
8 <pyof.v0x04.common.action.ActionExperimenter object at 0x10bc078c0>
>>>

The ActionHeader will be its correct size:

>>> a = ActionHeader(action_type=ActionType.OFPAT_OUTPUT, length=4)
>>> a.pack()
b'\x00\x00\x00\x04'
>>> a.get_size()
4
>>>

End-to-End Tests

Please refer to the results presented here: #110

The end-to-end tests were executed with all PRs stacked

[viniarck]

Nicely done @italovalcy, thanks for finding this and patching it. Looks good to me, I'll leave pre-approved. Before merging, make sure to push unit tests too though, we need coverage for this new added part (the examples you provided on local tests are great)