shellcheck: suppress also info and style findings

... so that we get equivalent scan results to the old version
of the shellcheck plug-in.

Related: https://issues.redhat.com/browse/OSH-655
Closes: #182

py/plugins/shellcheck.py

@@ -25,7 +25,7 @@
 SHELLCHECK_CAP_DIR = "/builddir/shellcheck-results"
 
 FILTER_CMD = "csgrep --mode=json --remove-duplicates --quiet " \
-        "--invert-match --event '^note|warning\\[SC1090\\]'"
+        "--invert-match --event '^info|note|style|warning\\[SC1090\\]'"
 
 # default maximum number of scripts scanned by a single shellcheck process
 DEFAULT_SC_BATCH = 1