Squish: Remove outdated version check

To build Creator, you need Qt 5.6 at least.
To test Qt 5.6 you need Squish 6 at least.

Change-Id: I5b4c08da64df749961544c25f3ed691ff56d2cc0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

tests/system/shared/utils.py

@@ -665,7 +665,3 @@ def getHelpTitle():
         return str(hv.title)
     except:
         return str(hv.documentTitle)
-
-def canTestEmbeddedQtQuick():
-    return (squishinfo.major * 0x10000 + squishinfo.minor * 0x100
-            + squishinfo.patch) > 0x050100