x/tools/gopls: release version v0.10.0

[findleyr]

This issue tracks progress toward releasing gopls@v0.10.0

• create gopls-release-branch.0.10
• merge master into gopls-release-branch.0.10
• update hard-coded version
• update go.mod/go.sum (remove x/tools replace, update x/tools version)
• tag gopls/v0.10.0-pre.1
• update Github milestone
• write release notes
• smoke test features
• tag gopls/v0.10.0
• update dependencies in master for the next release

[gopherbot]

Change https://go.dev/cl/442778 mentions this issue: all: update codereview.cfg for gopls-release-branch.0.10

[gopherbot]

Change https://go.dev/cl/442779 mentions this issue: gopls: update hard-coded version for v0.10.0

[gopherbot]

Change https://go.dev/cl/442915 mentions this issue: gopls: update go.mod for v0.10.0

[gopherbot]

Change https://go.dev/cl/444541 mentions this issue: gopls: update go.mod and go.sum for v0.10.0-pre.2

[gopherbot]

Change https://go.dev/cl/445818 mentions this issue: gopls: update go.mod for v0.10.0-pre.3

[gopherbot]

Change https://go.dev/cl/446184 mentions this issue: gopls: update go.mod for v0.10.0-pre.4