types/logger: fix test failure I missed earlier

I didn't see the race builder fail on CI earlier in 590c693b9.
This fixes the test.

Updates #greenci

Change-Id: I9f271bfadfc29b010226b55bf6647f35f03730b1
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

types/logger/logger_test.go

@@ -15,6 +15,7 @@ import (
 
 	qt "github.com/frankban/quicktest"
 	"tailscale.com/tailcfg"
+	"tailscale.com/version"
 )
 
 func TestFuncWriter(t *testing.T) {
@@ -238,6 +239,12 @@ func TestAsJSON(t *testing.T) {
 		t.Errorf("for marshal error, got %#q; want %#q", got, wantErr)
 	}
 
+	if version.IsRace() {
+		// skip the rest of the test in race mode;
+		// race mode causes more allocs which we don't care about.
+		return
+	}
+
 	var buf bytes.Buffer
 	n := int(testing.AllocsPerRun(1000, func() {
 		buf.Reset()