fix(deps): update jjwt.version to v0.12.6

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
io.jsonwebtoken:jjwt-jackson	0.12.5 -> 0.12.6
io.jsonwebtoken:jjwt-impl	0.12.5 -> 0.12.6
io.jsonwebtoken:jjwt-api	0.12.5 -> 0.12.6

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Release Notes

jwtk/jjwt (io.jsonwebtoken:jjwt-jackson)

v0.12.6

Compare Source

This patch release:

• Ensures that after successful JWS signature verification, an application-configured Base64Url Decoder output is used to construct a Jws instance (instead of JJWT's default decoder). See Issue 947.
• Fixes a decompression memory leak in concurrent/multi-threaded environments introduced in 0.12.0 when decompressing JWTs with a zip header of GZIP. See Issue 949.
• Upgrades BouncyCastle to 1.78 via PR 941.

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