Abbreviated options are not matched if value attached with '=' separator (like -x=3)

[remkop]

Related to #1159: Abbreviated options are not matched if value attached with '=' separator.

Test to reproduce the issue:

@Test
public void testAbbreviatedOptionWithAttachedValue() {
    @Command
    class Bean {
        @Option(names = "--xxx-yyy")
        int x;
    }
    Bean bean = new Bean();
    CommandLine cmd = new CommandLine(bean);
    cmd.setAbbreviatedOptionsAllowed(true);
    cmd.parseArgs("--x-y=123");
    assertEquals(123, bean.x);
}

The above test should pass but as of picocli 4.5.1, it fails with error UnmatchedArgumentException: Unknown option: '--x-y=123'.

[remkop]

@metacosm Picocli 4.5.2, which contains the fix for this issue, has been released.
Enjoy!