Remove caching in deployment scripts

[tobiasdiez]

Recently our build script fails and often the reason is a problem with the cache. https://github.com/JabRef/jabref/runs/597567964 Let's see if it works without caching.

• Change in CHANGELOG.md described (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked documentation: Is the information available and up to date? If not created an issue at https://github.com/JabRef/user-documentation/issues or, even better, submitted a pull request to the documentation repository.

[tobiasdiez]

I'll merge now directly because the build is successful and actually faster than with the cache (https://github.com/JabRef/jabref/runs/597567973?check_suite_focus=true needed 5min longer because restoring / saving the cache takes quite long).

[koppor]

Because of this, we are blocked by jcenter or maven central, because of high traffic load.

Build runtime image
4m 57s
	at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:38)
* What went wrong:
Execution failed for task ':compileJava'.
> Could not resolve all files for configuration ':compileClasspath'.
   > Could not resolve org.apache.logging.log4j:log4j-jcl:3.0.0-SNAPSHOT.
     Required by:
         project :
      > Could not resolve org.apache.logging.log4j:log4j-jcl:3.0.0-SNAPSHOT.
         > Could not get resource 'https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-jcl/3.0.0-SNAPSHOT/log4j-jcl-3.0.0-20200510.182830-557.pom'.
            > Could not GET 'https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-jcl/3.0.0-SNAPSHOT/log4j-jcl-3.0.0-20200510.182830-557.pom'.
               > Read timed out
   > Could not resolve org.apache.logging.log4j:log4j-slf4j18-impl:3.0.0-SNAPSHOT.
     Required by:
         project :
      > Could not resolve org.apache.logging.log4j:log4j-slf4j18-impl:3.0.0-SNAPSHOT.
         > Unable to load Maven meta-data from https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-slf4j18-impl/3.0.0-SNAPSHOT/maven-metadata.xml.
            > Could not get resource 'https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-slf4j18-impl/3.0.0-SNAPSHOT/maven-metadata.xml'.
               > Could not GET 'https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-slf4j18-impl/3.0.0-SNAPSHOT/maven-metadata.xml'.
                  > Connection reset
   > Could not resolve org.apache.logging.log4j:log4j-plugins:3.0.0-SNAPSHOT.
     Required by:
         project :
      > Could not resolve org.apache.logging.log4j:log4j-plugins:3.0.0-SNAPSHOT.
         > Unable to load Maven meta-data from https://repository.apache.org/snapshots/org/apache/logging/log4j/log4j-plugins/3.0.0-SNAPSHOT/maven-metadata.xml.

[koppor]

Tweeted about it - let's see

.@github Is there a blog entry or help page explaining why building with #githubactions caching is considerably slower than without any cache? Refs #6309.

— Oliver Kopp (@koppor) May 12, 2020