Planner checks wrong info to determine if an Op needs to run on PEM

[sync-by-unito[bot]]

In the distributed planner, inside the stitcher, there is a check for whether an Op has to run on PEM or not. Currently, that check just checks if the op has any metadata type set. This is not correct though since some metadata funcs have to happen on Kelvin (eg. ip_to_pod_id). This leads to a spurious ERROR message being logged, and perhaps in some cases the grpc bridges being incorrect.

┆Issue is synchronized with this Jira Bug by Unito