SuSE/RPM merge specfiles and only build a single rpm for RH/SuSE

[philfry]

This PR contains the following changes:

• merge rpm and SuSE specfiles
• remove zypper repository file, analogous to #1202
• remove SuSE build script
• re-add lost %dir %{_datadir}/%{name}

I'm not sure how the publishing works, though. Probably I'll need a little help here.

Testing done

# import the rpm signing key and announce it to rpm
gpg --import credentials/test.secret.gpg
echo '%_gpg_name Bogus Test (This is test only key) <[email protected]>' > ~/.rpmmacros

# remove the msi thingy
sed -i '/^export MSI/d' setup.mk

# get the war
export ver="2.414.1"
wget -c https://get.jenkins.io/war-stable/${ver}/jenkins.war

# build the rpm
WAR=${PWD}/jenkins.war make rpm BRAND=./branding/jenkins.mk BUILDENV=./env/release.mk VERSION=${ver}

# as I use podman instead of docker I needed some minor adaptions
sed -i 's/docker/podman/' requirements.txt molecule/default/molecule.yml
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt

# get the dokken images
podman pull docker.io/dokken/{oraclelinux-{8,9},opensuse-leap-15}:latest

# run the tests
molecule test -p oraclelinux-8
molecule test -p oraclelinux-9
molecule test -p opensuse-leap-15

PLAY RECAP *********************************************************************
oraclelinux-8              : ok=16   changed=4    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
oraclelinux-9              : ok=10   changed=4    unreachable=0    failed=0    skipped=3    rescued=0    ignored=0
opensuse-leap-15           : ok=16   changed=4    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

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- [x] Ensure you have provided tests - that demonstrates feature works or fixes the issue

Fixes: #419