[testrunner] Add missing comma

Without the comma, the two strings '--no-enable-sse3' and
'--noenable-ssse3' will be concatenated, resulting in missing detection
for the no_simd_hardware flag.

R=liviurau@chromium.org

Bug: v8:12521
Change-Id: Icbdc5e8057d1eeead472f76efd52c379bffbe5b6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3372914Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78528}

tools/testrunner/base_runner.py

@@ -668,7 +668,7 @@ class BaseTestRunner(object):
 
     no_simd_hardware = any(
         i in options.extra_flags for i in ['--noenable-sse3',
-                                           '--no-enable-sse3'
+                                           '--no-enable-sse3',
                                            '--noenable-ssse3',
                                            '--no-enable-ssse3',
                                            '--noenable-sse4-1',