Correct external application properties load order

[MikeN123]

It seems the documentation is showing the wrong order for configuration properties.

The correct order judging from ConfigDataEnvironment and the remainder of the documentation is:

		locations.add(ConfigDataLocation.of("optional:classpath:/"));
		locations.add(ConfigDataLocation.of("optional:classpath:/config/"));
		locations.add(ConfigDataLocation.of("optional:file:./"));
		locations.add(ConfigDataLocation.of("optional:file:./config/*/"));
		locations.add(ConfigDataLocation.of("optional:file:./config/"));

But the documentation states the subdirectories of ./config are loaded last. I have corrected this and added 'in the current directory' to make sure everyone understands which subdirectories are meant.

I have not verified this is actually the correct loading order, but the code seems clear enough to me.

[philwebb]

Thanks for the PR @MikeN123. After some discussion we think it would be better to change the code rather than the docs. I've opened #24308 to deal with that.