Give sqlite compatibility warning a distinct warning code
Give sqlite compatibility warning a distinct warning code

This prevents the fallback warning from interfering with the test wagtail.search.tests.test_indexed_class.TestSearchFields.test_checking_core_page_fields_are_indexed

zerolab/wagtail,rsalmaso/wagtail,jnns/wagtail,mixxorz/wagtail,wagtail/wagtail,zerolab/wagtail,jnns/wagtail,thenewguy/wagtail,wagtail/wagtail,mixxorz/wagtail,wagtail/wagtail,mixxorz/wagtail,thenewguy/wagtail,zerolab/wagtail,mixxorz/wagtail,wagtail/wagtail,thenewguy/wagtail,thenewguy/wagtail,wagtail/wagtail,zerolab/wagtail,jnns/wagtail,rsalmaso/wagtail,zerolab/wagtail,rsalmaso/wagtail,jnns/wagtail,mixxorz/wagtail,rsalmaso/wagtail,thenewguy/wagtail,rsalmaso/wagtail