fix(input): make maxlength and minlength work with non-string values

[ssergio198]

Request Type: bug

How to reproduce:

Component(s): misc core

Impact: small

Complexity: small

This issue is related to:

Detailed Description:

Other Comments:

Validity for inputs with maxlength attribute and an underlying non-string model value is always false: e.g. the length property for a numeric data type returns undefined

[mary-poppins]

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[mary-poppins]

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[Narretz]

Duplicate of #7968