deps: update x/tools & gopls to 8f301ca0 (#1079)

* internal/lsp: more careful error handling for semantic tokens 8f301ca0
* internal/lsp: exit graceful for modfiles in semantic tokens 09ab05b0
* gopls/internal/regtest: add a failing regtest for vscode-go#1489 cd1be5db
* internal/lsp: get file URI from beginFileRequest in SemanticTokens 57c3a74c
* go/analysis/passes/sigchanyzer: copy to avoid modifying the AST 8287d5da
* internal/lsp/cache: add missing error checks 9dfac01d
* all: update tests to use 'go mod download all' to populate go.sum be4aaae4
* internal/lsp/cache: trim more stuff in ParseExported mode cd1d0887
* internal/lsp: in semantic tokens, better distinguish between types and variables 2db0265c
* all: update all dependencies except for sergi/go-diff and golang.org/x/net 9cddb0ea
* internal/typeparams: a new helper library for working with generic code 18795da8
* internal/lsp/source/completion: avoid a panic in package completion 79d39ff5
* internal/lsp/debug: add a facility to track known bugs fa055457
* internal/lsp: do not reinitialize the workspace for didOpen events 5a667787
* internal/lsp: fix no definition when importShortcut is link 0185c7ed
* go/packages: in overlay_test, allow test variant in second_file case ecb73924
* godoc/static: add gopher/pkg.png image f05e9124