Bump Maven dependencies and plugins

pom.xml

@@ -210,7 +210,7 @@
 		<dependency>
 			<groupId>com.sun.mail</groupId>
 			<artifactId>javax.mail</artifactId>
-			<version>1.6.0</version>
+			<version>1.6.1</version>
 		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
@@ -309,7 +309,7 @@
 		<dependency>
 			<groupId>org.checkerframework</groupId>
 			<artifactId>checker-qual</artifactId>
-			<version>2.3.1</version>
+			<version>2.4.0</version>
 		</dependency>
 	</dependencies>
 
@@ -379,7 +379,7 @@
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-surefire-plugin</artifactId>
-				<version>2.20.1</version>
+				<version>2.21.0</version>
 			</plugin>
 			<plugin>
 				<groupId>org.jacoco</groupId>