Use mbedTLS 3.6.2 released a few days ago (Oct 15, 2024)

[DL6ER]

What does this implement/fix?

See title. Quoting from https://github.com/Mbed-TLS/mbedtls/releases/tag/mbedtls-3.6.2:

This release of Mbed TLS provides the fix for a security vulnerability.

Mbed TLS 3.6 is a long-term support (LTS) branch. It will be supported with bug-fixes and security fixes until at least March 2027.

• Fix a buffer underrun in mbedtls_pk_write_key_der() when
  called on an opaque key, MBEDTLS_USE_PSA_CRYPTO is enabled,
  and the output buffer is smaller than the actual output.
• Fix a related buffer underrun in mbedtls_pk_write_key_pem()
  when called on an opaque RSA key, MBEDTLS_USE_PSA_CRYPTO is enabled
  and MBEDTLS_MPI_MAX_SIZE is smaller than needed for a 4096-bit RSA key.
  CVE-2024-49195

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Related issue or feature (if applicable): N/A

Pull request in docs with documentation (if applicable): N/A

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