Add delete to handlers

CURA-6096

cura/Settings/DatabaseHandlers/IntentDatabaseHandler.py

@@ -18,7 +18,8 @@ class IntentDatabaseHandler(DatabaseMetadataContainerController):
                                 setting_version = ?
                             WHERE id = ?
                         """,
-            select_query = "SELECT * FROM intents where id = ?",
+            select_query = "SELECT * FROM intents WHERE id = ?",
+            delete_query = "DELETE FROM intents WHERE id = ?",
             table_query="""CREATE TABLE intents
                (
                    id text,

cura/Settings/DatabaseHandlers/QualityDatabaseHandler.py

@@ -18,7 +18,8 @@ class QualityDatabaseHandler(DatabaseMetadataContainerController):
                                     setting_version = ?
                                 WHERE id = ?
                             """,
-            select_query = "SELECT * FROM qualities where id = ?",
+            select_query = "SELECT * FROM qualities WHERE id = ?",
+            delete_query = "DELETE FROM qualities WHERE id = ?",
             table_query = """CREATE TABLE qualities
                 (
                     id text,

cura/Settings/DatabaseHandlers/VariantDatabaseHandler.py

@@ -15,7 +15,8 @@ class VariantDatabaseHandler(DatabaseMetadataContainerController):
                                     setting_version = ?
                                 WHERE id = ?
                            """,
-            select_query= "SELECT * FROM variants where id = ?",
+            select_query = "SELECT * FROM variants WHERE id = ?",
+            delete_query = "DELETE FROM variants WHERE id = ?",
             table_query = """CREATE TABLE variants
                 (
                     id text,