Merge pull request #2261 from mybatis/dependabot/maven/org.postgresql…

…-postgresql-42.2.21

Bump postgresql from 42.2.20 to 42.2.21

pom.xml

@@ -240,7 +240,7 @@
     <dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
-      <version>42.2.20</version>
+      <version>42.2.21</version>
       <scope>test</scope>
     </dependency>
     <dependency>