gopls: update to 0.6.2.

Features

Shadow analyzer

This off-by-default analyzer flags shadowed variables. Learn more
in the Analyzers documentation.

Experimental

New keys for the GC details "annotations" setting

The previous keys were prefixed with "no" and meant to disable
certain GC details checks, which was inconsistent with the style
of our other settings maps. A warning will appear suggesting a
change to the new key name, but the old settings will continue to
work. Full details can be found in the annotations documentation.

Documentation

Improved documentation for available analyzers.

Improved documentation for Vim.

Fixes

Editing the go.mod file by hand (golang/go#42529)

This issue was previously marked as resolved, but it had not actually
been fixed. Package metadata will now only be invalidated when a
go.mod file is saved, so you will need to save before expecting
your changes to be propagated. This should significantly reduce
the number of go list calls (and therefore CPU utilization) as you
edit the go.mod file.

(wiz)