[PAGOPA-1967] feat: Update Stamp converter

[cap-ang]

List of Changes

• Update ConvertMarcaDaBolloToCtRichiestaMarcaDaBollo
• Add companyName to GetPaymentV2 response (mandatory field)

Motivation and Context

decode from base64 and keep the marshalling time base64 encoding for SANP compliance

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[sonarcloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

Comment this PR with update_code to update openapi.json and format the code. Consider to use pre-commit to format the code.

[andrea-deri]

Good job! 🚀