Replacing {require,assert}.{Nil,NotNil} with {require,assert}.{NoError,Error} in the store tests (when comparing errors) (#16886)

* Replacing require.Nil with require.NoError

* More replacements

* More Nil/NotNill to NoError/Error

* Other detected errors

* renaming apperr to err

* Removed not needed line

* Rename old appErr variables that are no longer model.AppError values

* Fixing tiny typo

* Reverting changes outside the store (accidentally added)

* Apply suggestions from code review

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

store/sqlstore/store_test.go

@@ -371,7 +371,7 @@ func TestGetDbVersion(t *testing.T) {
 			store := New(*settings, nil)
 
 			version, err := store.GetDbVersion(false)
-			require.Nil(t, err)
+			require.NoError(t, err)
 			require.Regexp(t, regexp.MustCompile(`\d+\.\d+(\.\d+)?`), version)
 		})
 	}