internal/lsp: fix typo on license year
internal/lsp: fix typo on license year

Change-Id: I5643ce049bad0dfb45405c06adc7c2eb46a394ac
Reviewed-on: https://go-review.googlesource.com/c/tools/+/177017
Reviewed-by: Rebecca Stambler <d7cf11e5f299d88ea8348366a9fc4f7c335c3afa@golang.org>
Run-TryBot: Rebecca Stambler <d7cf11e5f299d88ea8348366a9fc4f7c335c3afa@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools