install: allow instantiated units to be enabled via presets
    
    This patch implements https://github.com/systemd/systemd/issues/9421.
    
    The .preset file now is able to take a rule in the format of:(e.g)
    enable foo@.service bar0 bar1 bar2
    
    In the above example, when preset-all is called, all three instances of
    foo@bar0.service, foo@bar1.service and foo@bar2.service will be enabled.
    
    When preset is called on a single service(e.g: foo@bar1.service), only
    the mentioned one(foo@bar1.service) will be enabled.
    
    Tests are added for future regression.
    
    (cherry picked from commit 4c9565eea534cd233a913c8c21f7920dba229743)
    
    Resolves: #1812972
    
    patch_name: 0487-install-allow-instantiated-units-to-be-enabled-via-p.patch
    present_in_specfile: true
    location_in_specfile: 487
    squash_commits: true