crypto/x509: remove redundant check for nil in tests
Comparing err variable to be not nil is redundant in this case.
The code above ensures that it is always not nil.
Updates #30208
Change-Id: I0a41601273de36a05d22270a743c0bdedeb1d0bf
GitHub-Last-Rev:
372e0fd48f90f33e266fbcdf2ccf87b9f1311c4f
GitHub-Pull-Request: golang/go#30213
Reviewed-on: https://go-review.googlesource.com/c/162439
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>