A workaround for this is to disable file watchers:
(setq lsp-enable-file-watchers nil)
... and then restart the workspace:
I'm not sure if this effectively disables a useful feature, but I can't get it to work otherwise.
The solution was described here: https://github.com/golang/go/issues/38032
More about file watchers here: https://...
You can lengthen the timeout using the lsp-response-timeout option: https://emacs-lsp.github.io/lsp-mode/page/settings/mode/#lsp-response-timeout
Of course, what you really want to do is make gopls faster. Probably not much you can configure in Emacs to do that.
As mentioned in the comments, a workaround for this issue is to start emacs on a folder (or on nothing) instead of on a single source file.
This was discussed for VScode with gopls as backend here: https://stackoverflow.com/a/49977881/497180