Remove superfluous --using-cache option

[paulbalandan]

When using nexusphp/cs-config, the --using-cache is default true if not provided.
https://github.com/NexusPHP/cs-config/blob/e9092a9ab3a59c982bf0c79c89df36a7b2c0b86e/src/Factory.php#L122

[kenjis]

I don't know why, but the original setting was --using-cache=no.
And the option does not show in the help vendor/bin/php-cs-fixer --help.
So I leave the option to easily know the option name.

I'm fine with this PR.

[datamweb]

Related : #340

[MGatner]

It came from my default toolkit:
https://github.com/tattersoftware/codeigniter4-tools/blob/develop/src/composer.php#L121

These are primarily for my library development, since maintaining the development tools across 40 repos is a nightmare. These libraries are mostly pretty small so I prefer to run without cache as my default. I'm fine with speeding things up for Shield, which is a larger scope. Also good with removing the argument here after @paulbalandan's explanation.

[paulbalandan]

Are there blocking issues/concerns preventing the merge?

[MGatner]

No problems! There wasn't any activity after my comment so it didn't come back in my feed. Sorry!