Make dependency on java.desktop optional

[bowbahdoe]

There is only one place in commons-lang where anything from java.desktop is used, and that is AbstractCircuitBreaker.

This changes that code to lazily initialize its internal PropertyChangeSupport. This makes it so that it is safe to initialize and use that class without java.desktop on the module-path.

Upsides:

• Smaller jlinked images for every apache commons library
• No binary compatibility changes

Downsides:

• Likely a small performance hit
• It is possible for a user to give a null instance of PropertyChangeListener without depending on the java.desktop module, in which case the behavior of the method will change from "ignores null" to "fails"
• I do not know how to add a test for this to the junit suite. We'd have to run a subset of the tests without java.desktop present. Currently I am validating manually like so

$ mvn clean compile package
$ jlink --module-path target/commons-lang3-3.15.0-SNAPSHOT.jar --add-modules org.apache.commons.lang3,jdk.jshell --output jre
$ ./jre/bin/java --list-modules
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$ ./jre/bin/jshell

jshell> var breaker = new EventCountCircuitBreaker(1000, 1, java.util.concurrent.TimeUnit.SECONDS);
breaker ==> org.apache.commons.lang3.concurrent.EventCountCircuitBreaker@1ce92674

jshell> breaker.addChangeListener(null);
|  Error:
|  cannot access java.beans.PropertyChangeListener
|    class file for java.beans.PropertyChangeListener not found
|  breaker.addChangeListener(null);
|  ^-----------------------------^

Before

$ du -sh jre
125M    jre

$ ./jre/bin/java --list-modules
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After

$ du -sh jre
 88M    jre

$ ./jre/bin/java --list-modules
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[garydgregory]

-1: This looks too hacky and brittle to me as we do not have ways to prevent future changes from depending on java.desktop or other modules which would make this moot. For 4.0, we can talk about making Lang a java.base only module. TBD.

[garydgregory]

Closing: For 4.0, we can remove the dependency on java.desktop, probably.