mkosi: update opensuse commit reference

mkosi: update opensuse commit reference

*   8c025c3bdf Accepting request 1184267 from Base:System
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| * 735f8c4ba4 - Import commit 5a8eadd0c021758337a020c423f25a353bdb9b3c (merge of v255.8)   For a complete list of changes, visit:   https://github.com/openSUSE/systemd/compare/603cd1d4d81147d4f2eccd5e352064a4215119b4...5a8eadd0c021758337a020c423f25a353bdb9b3c - Drop 5003-Revert-run-pass-the-pty-slave-fd-to-transient-servic.patch as v255.8   contains the workaround (commit 639c922ede9485) for the broken commit   28459ba1f4df.
* | 37853fecc3 Accepting request 1183029 from Base:System
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* 638de11012 - Don't automatically clean unmodified config files up (bsc#1226415)
* 369c023c24 reorder one more time...
* ffa9f0ac80 reorder the runtime deps of the testsuite package so the format_spec_file thingy stop screwing up the spec file...
* 12c1190a79 fix rev 1529: the devel packages are really needed by the testsuite script to install the dlopened libs into the image
* ca8e7f54ce - systemd.spec: move a misplaced %endif in the testsuite sub-package.
* b7944f5b14 - Merge systemd-coredump back into the main package (bsc#1091684)
* 3fa0dea84a - Don't pull the devel packages in when installing the testsuite package.