getSearchStringEscape not allowed in the metadata method calls

## Driver version

2.1.0.31

## Redshift version

Doesn't matter

## Client Operating System

Doesn't matter

## JAVA/JVM version

Doesn't matter

## Table schema

Doesn't matter

## Problem description

2.1.0.31 adds a validation of the input parameter to DatabaseMetadata.get* calls. The WHITELIST pattern doesn't accept escape character which makes it impossible to escape passed argument.

## JDBC trace logs

## Reproduction code

Start by tracing the DatabaseMetadata.get* calls and the WHITELIST validation mentioned in the report. Reproduce the failure with an escaped argument and determine whether the metadata methods accept it while retaining input validation; done means the reported escaped input no longer fails validation.

Written by the indexing model from the issue text.