Fixes #148 - log4j stderr message about not finding a logging implementation when using jsign CLI

[davoustp]

This fix makes the suggestion from https://github.com/ebourg/jsign/issues/148#issuecomment-1555797023 permanent, by leveraging the log4j2 properties mechanism (instead of relying onto users to do it themselves, struggling with passing Java props to an executable jar).

Reference:

• Factory loading shortcut: https://github.com/apache/logging-log4j2/blob/9c234901e15c9e7f54e527e56d994aa100bc1cbf/log4j-api/src/main/java/org/apache/logging/log4j/LogManager.java#L72-L83

• Properties loading: https://github.com/apache/logging-log4j2/blob/9c234901e15c9e7f54e527e56d994aa100bc1cbf/log4j-api/src/main/java/org/apache/logging/log4j/util/PropertiesUtil.java#L131-L133

• Log4J properties filename: https://github.com/apache/logging-log4j2/blob/9c234901e15c9e7f54e527e56d994aa100bc1cbf/log4j-api/src/main/java/org/apache/logging/log4j/util/PropertiesUtil.java#L61

[ebourg]

Merci ! I guess the log4j2.loggerContextFactory property can be removed from jsign.sh and jsign.cmd too.

[davoustp]

Merci ! I guess the log4j2.loggerContextFactory property can be removed from jsign.sh and jsign.cmd too.

De rien! ;-) I did commit this small change as well (these files went under the radar).