Bundle: replace deprecated --path option with the path setting

What does this MR do and why?

bundle install --path option is deprecated and has been replaced with the path setting.

So this PR replaces any

bundle install --path vendor/ruby

by

bundle config set --local path 'vendor/ruby'
bundle install

in the cache documentation page.

References

https://bundler.io/man/bundle-install.1.html

other references:

• Bundler 2.1 changelog - CLI deprecations

Related issues

None

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