Remove GitHub Workflows on main branch

[apupier]

Description

• The main, 3.x and 4.x branches are built on Apache Software Foundation Jenkins CI.
• The build for main branch was broken for 2 months already on GitHub

see discussion here https://camel.zulipchat.com/#narrow/stream/364655-camel-core-dev/topic/Reformat.20and.20build.20job.20on.20main.20branch.20on.20GitHub.20CI.20is.20KO/near/442541978

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

[apupier]

the workflows were also responsible to reformat.

TODO: check that it is done on Apache CI (or in another way)

[orpiske]

LGTM.

IIRC, these were used in conjunction with the regen bot ... which would open PRs whenever we broke the formatting somehow.

I think this is not working anymore, so it should be OK to remove.