Remove unnecessary SQL mode check from wp db query command

This check was causing authentication failures when custom connection
parameters (like --host) were passed, because get_current_sql_modes()
ignored those parameters. The check is also unnecessary since wp db query
doesn't use WPDB directly, and was inconsistently applied (skipped for STDIN).

Co-authored-by: swissspidy <841956+swissspidy@users.noreply.github.com>

Author: Copilot

features/db-query.feature

@@ -84,31 +84,4 @@ Feature: Query the database with WordPress' MySQL config
     When I try `wp db query --no-defaults --debug`
     Then STDERR should match #Debug \(db\): Running shell command: /usr/bin/env (mysql|mariadb) --no-defaults --no-auto-rehash#
 
-  Scenario: SQL modes do not include any of the modes incompatible with WordPress
-    Given a WP install
 
-    When I try `wp db query 'SELECT @@SESSION.sql_mode;' --debug`
-    Then STDOUT should not contain:
-      """
-      NO_ZERO_DATE
-      """
-    And STDOUT should not contain:
-      """
-      ONLY_FULL_GROUP_BY
-      """
-    And STDOUT should not contain:
-      """
-      STRICT_TRANS_TABLES
-      """
-    And STDOUT should not contain:
-      """
-      STRICT_ALL_TABLES
-      """
-    And STDOUT should not contain:
-      """
-      TRADITIONAL
-      """
-    And STDOUT should not contain:
-      """
-      ANSI
-      """

src/DB_Command.php

@@ -533,11 +533,6 @@ public function query( $args, $assoc_args ) {
 			$assoc_args['execute'] = $args[0];
 		}
 
-		if ( isset( $assoc_args['execute'] ) ) {
-			// Ensure that the SQL mode is compatible with WPDB.
-			$assoc_args['execute'] = $this->get_sql_mode_query( $assoc_args ) . $assoc_args['execute'];
-		}
-
 		$is_row_modifying_query = isset( $assoc_args['execute'] ) && preg_match( '/\b(UPDATE|DELETE|INSERT|REPLACE|LOAD DATA)\b/i', $assoc_args['execute'] );
 
 		if ( $is_row_modifying_query ) {