Bump spring.version from 5.1.8.RELEASE to 5.3.1 in /k2-parent#12

dependabot[bot] wants to merge 1 commit intomasterkatari/k2:masterfrom

dependabot/maven/k2-parent/spring.version-5.3.1katari/k2:dependabot/maven/k2-parent/spring.version-5.3.1Copy head branch name to clipboard