Change key length to 600char in tests.

This is to reflect changes from #25 in tests.

Author: G8XSU

app/src/test/java/org/vss/impl/postgres/PostgresBackendImplIntegrationTest.java

@@ -48,7 +48,7 @@ void destroy() throws Exception {
   private void createTable(DSLContext dslContext) {
     dslContext.execute("CREATE TABLE vss_db ("
         + "store_id character varying(120) NOT NULL CHECK (store_id <> ''),"
-        + "key character varying(120) NOT NULL,"
+        + "key character varying(600) NOT NULL,"
         + "value bytea NULL,"
         + "version bigint NOT NULL,"
         + "created_at TIMESTAMP WITH TIME ZONE,"