Example of core update command

[ernilambar]

Bug Report

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Describe the current, buggy behavior

wp core update has following example:

# Update WordPress to latest version of 3.8 release
$ wp core update --version=3.8 ../latest.zip

When zip file is given, --version seems to be extraneous here I guess.

[danielbachhuber]

Yeah, we can remove it from the example.