Hide orange measure line and points while measure tool is inactive

[raymondnijssen]

Description

When selecting another tool while using the measure tool, the measure dialog disappeares but the orange rubberband lines and points stayed visible. They could only be removed by reselecting the measure tool and close the dialog, being confusing to the user.

This new code makes the rubberband hidden while not using the measure tool and shows it when reselecting the tool.

Checklist

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[m-kuhn]

Should this be backported?

[raymondnijssen]

@m-kuhn Would be nice to backport it :)

[backporting]

The backport to release-3_4 failed:

Reference already exists