Fix DeprecationWarnings by updating key type property usage in tests

[Subham-KRLX]

Fixes #1483.

Replaced deprecated key.key_type with key.kty in test files to remove DeprecationWarnings and ensure compatibility with latest dependencies.

Single change (remove DeprecationWarnings).

[dopry]

@Subham-KRLX for context, can you link to the documentation regarding the deprecation of key_type here in the issue?

[Subham-KRLX]

Hi @dopry, this change is based on the official JSON Web Key spec (RFC 7517, Section 4.1) which mandates "kty" as the standard parameter for key type. The older key_type property in libraries like jwcrypto has been deprecated and now triggers warnings with .kty being the correct standards-compliant attribute. Updating the tests removes these DeprecationWarnings ensures compatibility with the latest dependencies and aligns with the JWK specification.

[dopry]

I'm familiar with the spec change. I was specifically wondering which one of our dependencies is throwing this deprecation warning and is a mention of the deprecation available in their changelog or release notes.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[Subham-KRLX]

The warning comes from the jwcrypto library.
Since v1.5 key_type is deprecated in favour of the RFC 7517‑compliant kty attribute as noted in their changelog.