[Minor-Bug] Replace deprecated method formatLocalized()

[maurohmartinez]

WHY

BEFORE - What was wrong? What was happening before this PR?

Some users see logger entries created due to the use of the deprecated method formatLocalized(). Issue reported here

AFTER - What is happening after this PR?

No more logger entries will be created.

HOW

How did you achieve that, in technical terms?

Method formatLocalized() is replaced with isoFormat().

Is it a breaking change or non-breaking change?

Non-breaking.

How can we test the before & after?

Just created couple of errors and checked them on Log Manager.

[welcome[bot]]

BOOM! Your first PR with us, thank you so much! Someone will take a look at it shortly.

Please keep in mind that:

• if this constitutes a breaking change, it might take quite a while for this to get merged; we try to emulate the Laravel release cycle as much as possible, so developers can upgrade both software once; this means a new big release every ~6 months;
• even if it's a non-breaking change, it might take a few days/weeks for the PR to get merged; unless it's a no-brainer, we like to have some community feedback on new features, before we merge them; this leads to higher-quality code, in the end; we learnt this the hard way :-)
• not all PRs get merged; sometimes we just have to hold out new features, to keep the packages lean; sometimes we don't include features that only apply to niche use cases;
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Thank you!

-- Justin Case The Backpack Robot

[tabacitu]

@maurohmartinez if this is ready for @pxpm to review again, remember to remove yourself from Assigned and put Pedro again. That way, it's easy for everybody to know what they should work on first - we look at "This week". We see our face, it's ours.

[welcome[bot]]

WHOOP-WHOOP! Congrats, your first PR on this repo has officialy been merged.

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