[IMP] uom_unece: Change unit code from C62 to PCE

[Rad0van]

According to https://www.gs1us.org/resources/data-hub-help-center/unit-of-measure-codes C62 means one while PCE means piece. I think PCE is correct as for example dozen is encoded as DPC meaning dozen piece.

[OCA-git-bot]

Hi @astirpe, @alexis-via,
some modules you are maintaining are being modified, check this out!

[pedrobaeza]

Please follow commit message guidelines: https://github.com/OCA/odoo-community.org/blob/master/website/Contribution/CONTRIBUTING.rst#commit-message

[Rad0van]

Please follow commit message guidelines: https://github.com/OCA/odoo-community.org/blob/master/website/Contribution/CONTRIBUTING.rst#commit-message

Thanks Pedro for reminder. Need to remind this once for all.

[github-actions]

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[bosd]

Actually the PCE is the old code.
The new recomended code is H87.
See:
https://www.gs1.org/standards/eancom/eancom-2002-edition-2016/eancom-syntax-3
click on:
Part III: Data elements & code sets directory
then go to:
2. Index by data element name
search for:
Measurement unit code

Then you will reach this page..

Measurement unit code

Where the recomended codes are explained.

[bosd]

Suggested change

	<field name="unece_code">PCE</field>
	<field name="unece_code">H87</field>

[bosd]

We need a migration script for this change as well.