fix(compute): register the dummy pool driver under its own kind (#539)

The gcn_machine_pool_driver entry point was registered as
"DummyPoolDriver" instead of "dummy", so it never matched
DummyPoolDriverSpec.KIND and could never be loaded - unlike its
"libvirt" sibling entry, which correctly used the driver spec's KIND
as the entry point name.

Author: VasilyStepanov

pyproject.toml

@@ -161,7 +161,7 @@ ec-bootstrap-templates = "exordos_core.cmd.bootstrap_templates:main"
 exordos-repo-proxy-gservice = "exordos_core.cmd.repo_proxy_gservice:main"
 
 [project.entry-points."gcn_machine_pool_driver"]
-DummyPoolDriver = "exordos_core.compute.pool.drivers.base:DummyPoolDriver"
+dummy = "exordos_core.compute.pool.drivers.base:DummyPoolDriver"
 libvirt = "exordos_core.compute.pool.drivers.libvirt:LibvirtPoolDriver"
 
 [project.entry-points."gcn_network_driver"]