fix(docs): add code notation

[squakez]

Fix the warning check:

YN0000: [build:antora  ] [build:antora-perf] [07:04:34.320] WARN (asciidoctor): skipping reference to missing attribute: color

Description

Target

• I checked that the commit is targeting the correct branch (note that Camel 3 uses camel-3.x, whereas Camel 4 uses the main branch)

Tracking

• If this is a large change, bug fix, or code improvement, I checked there is a JIRA issue filed for the change (usually before you start working on it).

Apache Camel coding standards and style

• I checked that each commit in the pull request has a meaningful subject line and body.

• I have run mvn clean install -DskipTests locally and I have committed all auto-generated changes