libjwt: update to 3.3.2

libjwt: update to 3.3.2

Major version jump from 1.17.1 to 3.3.2.

libjwt 3.x is a substantial rewrite:
 * New backend abstraction supporting OpenSSL, GnuTLS and MbedTLS
   crypto libraries (selected at build time).
 * New JWK and JWKS APIs for key handling with full RFC 7517 support.
 * Improved error handling and reporting.
 * EdDSA signature support (Ed25519, Ed448).
 * Optional libcurl integration for fetching JWKS from a URL.
 * Many API additions while keeping backwards-compatible semantics
   for the most common HMAC/RSA/ECDSA operations.

Force OpenSSL backend (-DWITH_GNUTLS=OFF -DWITH_MBEDTLS=OFF) since
libopenssl is already a dependency, avoiding pulling in libgnutls.
Disable -DWITH_TESTS=OFF since the testsuite is not relevant for
embedded targets.

Link: https://github.com/benmcollins/libjwt/releases/tag/v3.3.2
Signed-off-by: Daniel Golle <redacted>