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#### What I did
`generic_config_updater/*` `sonic-mgmt` tests need topo-asic definitions to work properly. The definition for the topo `Arista-7260CX3-Q44` is missing.

Adding the mapping for `Arista-7260CX3-Q44`.
*Needs backport to 202511*.

#### How I did it
Adding the HwSKU entry `Arista-7260CX3-Q44` to `generic_config_updater/gcu_field_operation_validators.conf.json`.

#### How to verify it
generic_config_updater/test_pfcwd_status.py no longer fails on 202511.

Signed-off-by: Sonic Build Admin <sonicbld@microsoft.com>

#### Previous command output (if the output of a command-line utility has changed)

#### New command output (if the output of a command-line utility has changed)