filer: default the filemeta CREATE TABLE for postgres2/mysql2 when createTable is unset (#10232)

* postgres2: default the filemeta CREATE TABLE when createTable is unset

An empty createTable rendered through fmt.Sprintf produced
%!(EXTRA string=filemeta), which Postgres rejected with a syntax error at
init. Fall back to a working template so a minimal config bootstraps.

* mysql2: default the filemeta CREATE TABLE when createTable is unset

Same empty-template failure the postgres2 path had: an unset createTable
rendered to %!(EXTRA string=filemeta) and MySQL rejected it at init.
Fall back to a working template.

weed/filer/postgres2/postgres2_store.go

@@ -63,6 +63,9 @@ func (store *PostgresStore2) Initialize(configuration util.Configuration, prefix
 func (store *PostgresStore2) initialize(createTable, upsertQuery string, enableUpsert bool, user, password, hostname string, port int, database, schema, sslmode, sslcert, sslkey, sslrootcert, sslcrl string, pgbouncerCompatible bool, maxIdle, maxOpen, maxLifetimeSeconds int) (err error) {
 
 	store.SupportBucketTable = true
+	if createTable == "" {
+		createTable = postgres.DefaultCreateTableQuery
+	}
 	if !enableUpsert {
 		upsertQuery = ""
 	} else if upsertQuery == "" {