modfile.File.SetRequire panics on duplicate requires with conflicting
versions. Avoid the panic by returning an error in this case.
Skip directness diagnostics that run into this error, rather than
invalidating all diagnostics.
Fixesgolang/go#50425
Change-Id: Ic6379ecc48581e7fd7b470ed295e449833c351dd
Reviewed-on: https://go-review.googlesource.com/c/tools/+/376394
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>