CAMEL-23760: camel-oauth - sync upgrade-guide entry to 4.18/4.14 guides on main

[oscerd]

Description

Documentation sync follow-up for CAMEL-23760 (camel-oauth UserProfile JWK-set fail-closed verification, merged for 4.21.0 in #24032).

Per the backport upgrade-guide policy, the version-specific camel-4x-upgrade-guide-4_XX.adoc files on main are the canonical history. The camel-oauth change is fixVersioned for 4.18.3 and 4.14.8, so this adds the matching camel-oauth entry to:

• camel-4x-upgrade-guide-4_18.adoc (Upgrading from 4.18.1 to 4.18.3)
• camel-4x-upgrade-guide-4_14.adoc (Upgrading from 4.14.3 to 4.14.8)

The code backports to the camel-4.18.x / camel-4.14.x branches will follow.

Claude Code on behalf of Andrea Cosentino.

🤖 Generated with Claude Code

[github-actions]

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[luigidemasi]

LGTM!

[github-actions]

🧪 CI tested the following changed modules:

• docs

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