Zeebe Simple Monitor 0.20.0

Changelog

• allows to configure the context-path (#209)
• (deps) dump spring-zeebe-starter from 0.24.0 to 0.26.2
• (deps) dump spring-boot-dependencies from 2.3.5 to 2.4.2
• (deps) bump hazelcast from 4.0.2 to 4.1