[prabhataravind]

What I did
Associate trap group only if trap action is copy or trap.
Why I did it
When using SN4600 as a leaf fanout switch, LACP trap action needs to be changed from "TRAP" to "FORWARD". However this will return an error when creating the host interface as shown in the details section below. In addition, per saihostif definitions, SAI_HOSTIF_TRAP_ATTR_TRAP_GROUP is only valid if SAI_HOSTIF_TRAP_ATTR_PACKET_ACTION == SAI_PACKET_ACTION_TRAP or SAI_HOSTIF_TRAP_ATTR_PACKET_ACTION == SAI_PACKET_ACTION_COPY.
How I verified it
By setting LACP trap action to "FORWARD" and making sure no syncd/orchagent error is seen.
Details if related
ERR syncd#SDK: [SAI_UTILS.ERR] mlnx_sai_utils.c[1906]- sai_attribute_valid_condition_check: Attribute SAI_HOSTIF_TRAP_ATTR_TRAP_GROUP doesn't match a valid
conditions: {(SAI_HOSTIF_TRAP_ATTR_PACKET_ACTION : TRAP)
OR (SAI_HOSTIF_TRAP_ATTR_PACKET_ACTION : COPY)}
ERR syncd#SDK: [SAI_HOST_INTERFACE.ERR] mlnx_sai_host_interface.c[2039]- mlnx_create_hostif_trap: Failed attribs check
ERR syncd#SDK: :- sendApiResponse: api SAI_COMMON_API_CREATE failed in syncd mode: SAI_STATUS_FAILURE
ERR syncd#SDK: :- processQuadEvent: attr: SAI_HOSTIF_TRAP_ATTR_TRAP_TYPE: SAI_HOSTIF_TRAP_TYPE_LACP
ERR syncd#SDK: :- processQuadEvent: attr: SAI_HOSTIF_TRAP_ATTR_TRAP_GROUP: oid:0x11000000000baa
ERR syncd#SDK: :- processQuadEvent: attr: SAI_HOSTIF_TRAP_ATTR_PACKET_ACTION: SAI_PACKET_ACTION_FORWARD
ERR swss#orchagent: :- create: create status: SAI_STATUS_FAILURE
ERR swss#orchagent: :- applyAttributesToTrapIds: Failed to create trap 1, rv:-1
ERR swss#orchagent: :- trapGroupProcessTrapIdChange: Failed to set traps to trap group queue4_group1
ERR swss#orchagent: :- doTask: Processing copp task item failed, exiting.

[prsunny]

@prabhataravind , please update the description as per the template. Also add VS tests

[dgsudharsan]

Please add UT and description.
The main use case of CoPP is to trap or copy and apply rate limiting. What usecase does this PR address? Is it drop? If you need to drop traffic, can't regular ACLs be used?