Feature: add createCustomField resolver (#1698)

* Feature: add createCustomField resolver

* update mocks

* fix import

* invalidate workspace datasource cache after migration

* fix typo

server/src/tenant/metadata/field-metadata/field-metadata.util.ts

@@ -0,0 +1,9 @@
+/**
+ * Generate a column name from a field name removing unsupported characters.
+ *
+ * @param name string
+ * @returns string
+ */
+export function generateColumnName(name: string): string {
+  return name.toLowerCase().replace(/ /g, '_');
+}