Update CI server to use JDK 8u20 [SPR-12077]

[spring-projects-issues]

Stéphane Nicoll opened SPR-12077 and commented

Make sure the 4.1.GA compiles against the latest JDK

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No further details from SPR-12077

[spring-projects-issues]

Stéphane Nicoll commented

Java 8u20 has been installed in the CI environment.