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## Environment
**Liquibase Version**: `4.1.1`

**Liquibase Integration & Version**: Spring Boot

**Database Vendor & Version**: Postgres 12.3

**Operating System Type & Version**: Ubuntu 20.04

## Description
There's a regression after upgrading from `4.1.0` to `4.1.1` that is causing `StackOverflowError` while generating Postgres statement during processing a large SQL file-based changeset.  It seems to be a regression
introduced in #912  while trying to fix [CORE-3379](https://liquibase.jira.com/browse/CORE-3379).

## Steps To Reproduce
Create a changeset:

```xml
<changeSet id="StackOverflowError" author="goostleek">
    <sqlFile path="large.sql" relativeToChangelogFile="true"/>
</changeSet>
```

The `sqlFile` is ~200kb. It's been included in [the file](https://github.com/liquibase/liquibase/blob/2bb6acad174723e770f43411fbeae2a68e2af691/liquibase-core/src/test/resources/liquibase/change/long-statement.sql) in the PR #1508 which introduces a failing unit test presenting the error.

## Actual Behavior
`StackOverflowError` is thrown during SpringBoot application startup while applying the changest.

## Expected/Desired Behavior
The changeset is executed successfully like it was before upgrading to Liquibase 4.1.1.

## Additional Context
See #912, #1508


private String endDelimiter;
    private String sql;
    private String dbms;
    protected String encoding;
    protected AbstractSQLChange() {
        setStripComments(null);
        setSplitStatements(null);
    }
    public InputStream openSqlStream() throws IOException {
        return null;
    }
    @Override
    @DatabaseChangeProperty(since = "3.0", exampleValue = "h2, oracle")
    public String getDbms() {
        return dbms;
    }
    @Override
    public void setDbms(final String dbms) {
        this.dbms = dbms;
    }
    /**
     * {@inheritDoc}
     * @param database
     * @return always true (in AbstractSQLChange)
     */
    @Override
    public boolean supports(Database database) {
        return true;
    }
    @Override