[fix] google engine: results XPath

Seems google rolls out changes first on the `google.com` domain and later on the
"language" domains.  By example: yesterday [1] `google.com` did not work but
`google.de` and `google.fr` did work, today they do not work any longer and this
fix is needed on all domains.

Closes: https://github.com/searxng/searxng/issues/1628
[1] https://github.com/searxng/searxng/issues/1628#issuecomment-1208191816

searx/engines/google.py

@@ -113,7 +113,7 @@ filter_mapping = {0: 'off', 1: 'medium', 2: 'high'}
 # ------------------------
 
 # google results are grouped into <div class="jtfYYd ..." ../>
-results_xpath = '//div[contains(@class, "jtfYYd")]'
+results_xpath = '//div[contains(@class, "kvH3mc")]'
 
 # google *sections* are no usual *results*, we ignore them
 g_section_with_header = './g-section-with-header'