Retrieve the table handle only when dealing with a system table

[findinpath]

Description

This is a small usability improvement which aims to provide a more meaningful error message to the user in case that the user asks for an invalid metadata table corresponding to an existing Iceberg table.

assertQueryFailure(() -> onTrino().executeQuery("TABLE iceberg.default.\"" + tableName + "$invalid\""))
                .hasMessageMatching("\\QQuery failed (#\\E\\S+\\Q): Table '" + icebergTableName + "$invalid' redirected to '" + hiveTableName + "$invalid', but the target table '" + hiveTableName + "$invalid' does not exist");

Additional context and related issues

Release notes

(x) This is not user-visible or docs only and no release notes are required.
( ) Release notes are required, please propose a release note for me.
( ) Release notes are required, with the following suggested text:

[findepi]

Why is this "DO NOT MERGE"?
Does it also mean "DO NOT REVIEW"?

[findinpath]

Yes, at the moment is not reviewable. I made a false supposition while writing it.

[findinpath]

CI Hit #5427

[findinpath]

@ebyhr CPTAL at this PR ? It is pretty similar to what has been done for the $history metadata table in Delta.

[ebyhr]

CI hit #15187