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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


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                    if (read == -1) {
                        return true;
                    }
                    if (!isWhiteSpace(read)) {
                        if (!resizingBuffer.isEmpty()) {
                            byte[] buf = new byte[resizingBuffer.size()];
                            for (int i=0; i< resizingBuffer.size(); i++) {
                                buf[i] = resizingBuffer.get(i);
                            }
                            stream.unread(buf);
                        }
                        stream.unread(quickBuffer, 0, quickBufferUsed);
                        return false;
                    }
                }
            } finally {
                resizingBuffer.clear();
            }
        }
        private boolean isWhiteSpace(int read) {
            return (read == ' ') || (read == '\n') || (read == '\r') || (read == '\t');
        }
        @Override
        public void close() throws IOException {
            stream.close();
        }
    }
}