Start building against Spring Framework 5.3.31 snapshots

See gh-38283

Author: wilkinsona

gradle.properties

@@ -11,7 +11,7 @@ jacksonVersion=2.13.5
 junitJupiterVersion=5.8.2
 kotlinVersion=1.6.21
 mavenVersion=3.9.4
-springFrameworkVersion=5.3.30
+springFrameworkVersion=5.3.31-SNAPSHOT
 tomcatVersion=9.0.82
 
 kotlin.stdlib.default.dependency=false