Remove reference to %{java_home} from commands

[fridrich]

The %ant, %jar %javadoc %javac commands make little sense but they might be in spec files around the place. Make them just straight ant, jar, javadoc and javac as a stop-gap solution. Would be nice to echo before that they are deprecated, but that would be a lot of noise in the rpm build.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 91.00%. Comparing base (3471e50) to head (b9eaeab). Report is 17 commits behind head on master.

Additional details and impacted files

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[mizdebsk]

In Fedora and RHEL we do set %java_home macro and we want to use the commands from %java_home and not from $PATH. Therefore these macros are still relevant to us. Instead I propose to fall back to straight commands when %java_home is not defined. I'll open PR for that.

[mizdebsk]

My alternative proposal is at #132

[fridrich]

Closing in favour of #132