⬆️ Bump spring-webmvc from 5.2.8.RELEASE to 5.3.18

Bumps [spring-webmvc](https://github.com/spring-projects/spring-framework) from 5.2.8.RELEASE to 5.3.18.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](spring-projects/spring-framework@v5.2.8.RELEASE...v5.3.18)

---
updated-dependencies:
- dependency-name: org.springframework:spring-webmvc
  dependency-type: direct:production
...

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

Author: dependabot[bot]

pom.xml

@@ -15,7 +15,7 @@
 	    <maven.compiler.target>1.8</maven.compiler.target>
 
 		<weixin-java-mp.version>4.2.0</weixin-java-mp.version>
-		<spring.version>5.2.8.RELEASE</spring.version>
+		<spring.version>5.3.18</spring.version>
 		<spring-security.version>5.4.7</spring-security.version>
 		<slf4j.version>1.7.2</slf4j.version>
 		<aspectj.version>1.8.9</aspectj.version>