[release-branch.go1.15] net/http/fgci: skip flaky test

A test introduced in the security release is flaky due to a pre-existing
issue that does not qualify for backport itself.

Updates #41167
Fixes #41193

Change-Id: Ie6014e0796c1baee7b077881b5a799f9947fc9c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/252717
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/net/http/fcgi/fcgi_test.go b/src/net/http/fcgi/fcgi_test.go
index 4a27a12..59246c2 100644
--- a/src/net/http/fcgi/fcgi_test.go
+++ b/src/net/http/fcgi/fcgi_test.go
@@ -347,6 +347,7 @@
 }
 
 func TestResponseWriterSniffsContentType(t *testing.T) {
+	t.Skip("this test is flaky, see Issue 41167")
 	var tests = []struct {
 		name   string
 		body   string