add jetty-project 12.1.0.alpha1

[hboutemy]

https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/org/eclipse/jetty/jetty-project/README.md

[github-actions]

version=12.1.0.alpha1
ok=889
ko=0
ignored=1
koFiles=""
ignoredFiles="jetty-p2-12.1.0.alpha1-p2site.zip"
reference_java_version="22 (from MANIFEST.MF Build-Jdk-Spec)"
reference_os_name="Unix (from pom.properties newline)"

docker build -q -t ghcr.io/jvm-repo-rebuild/rb-ubuntu-jdk22-toolchains-22
	1:00.30 real,	0.13 user,	0.14 sys
docker build -q -t ghcr.io/jvm-repo-rebuild/rb-ubuntu-jdk22-toolchains-22-maven-3.9.6
	0:09.55 real,	0.06 user,	0.05 sys
docker build -q -t ghcr.io/jvm-repo-rebuild/rb-ubuntu-jdk22-toolchains-22-maven-3.9.6-runner
	0:12.18 real,	0.08 user,	0.04 sys
docker build -q -t ghcr.io/jvm-repo-rebuild/rb-ubuntu-jdk22-toolchains-22-maven-3.9.6-runner-utc-en_us-002
	0:15.13 real,	0.07 user,	0.05 sys
docker run --name rebuild-central --rm
	12:36.86 real,	0.36 user,	0.81 sys