sl15.4.conf and sles15sp4.conf set sle_version to 150300

[Ionic]

There's some weirdness going on with the SLE 15 SP4 and Leap 15.4 configs.

While SLE 15 SP4 doesn't even set sle_version to 150400, but only to 150300, the Leap 15.4 config at least tries to do so, but was later merged with the SLE 15 SP4 version in a weird way which resets sle_version to 150300.

I believe that the SLE 15 SP4 config is missing stuff from SUSE:SLE-15-SP4:GA, which is also supposed to be merged into the Leap 15.4 config file?

Upon closer inspection, it looks like the only missing part is actually the # COMMON BEGIN common part section from SUSE:SLE-15-SP4:GA. Maybe also stuff from SUSE:SLE-15-SP4:Update, but I don't know how this is handled. Maybe that's only supposed to get applied to the SLE 15 SP5/Leap 15.5 config files eventually, but not to the SLE 15 SP4/Leap 15.4 config files.