Delete format support in Explain physical plan sql queries

[abhioncbr]

Recently, we started supporting the physical plan for the queries based on the EXPLAIN IMPLEMENTATION PLAN.

However, the implemented solution supports different formats, which doesn't make sense. We already have discussed it. Based on it, this is just a minor follow-up issue to remove the format support in the physical plan queries.

labels: multistage

cc: @walterddr

[abhioncbr]

fix, #11179

[walterddr]

Good catch!