Bump checker-qual from 3.8.0 to 3.9.1 in /PgBulkInsert

Bumps [checker-qual](https://github.com/typetools/checker-framework) from 3.8.0 to 3.9.1.
- [Release notes](https://github.com/typetools/checker-framework/releases)
- [Changelog](https://github.com/typetools/checker-framework/blob/master/changelog.txt)
- [Commits](typetools/checker-framework@checker-framework-3.8.0...checker-framework-3.9.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

PgBulkInsert/pom.xml

@@ -221,7 +221,7 @@
             <scope>compile</scope>
             <groupId>org.checkerframework</groupId>
             <artifactId>checker-qual</artifactId>
-            <version>3.8.0</version>
+            <version>3.9.1</version>
         </dependency>
 
         <dependency>