software/ors-amarisoft: Workaround SlapOS Master inability to handle shared instances of multiple types

While upcoming SlapOS Master should be able to handle multiple types of
shared instances attached to the same main instance, current SlapOS
Master UI does not handle it well, and explicitly rejected to do so with
nexedi/slapos@dae3ad01 , which turned
json-schemas check failing for ors-amarisoft as

    FAIL: test_ors-amarisoft_software_cfg_json (slapos.test.test_json_schema.TestJSONSchemaValidation)
    ----------------------------------------------------------------------
    Traceback (most recent call last):
      File ".../slapos/slapos/test/test_json_schema.py", line 81, in run
        assert _software_type_tuple not in _viewed_software_type, \
    AssertionError: Duplicated software release on enb, shared: True

-> Work it around by adjusting software.cfg.json to use only one type of
shared instance for each main instance, and inside schema of that type
dispatch to all needed subtypes with oneOf.

This patch should be reverted when/if SlapOS Master starts to handle
shared instances of multiple types well.

/cc @tomo, @jhuge, @lu.xu, @xavier_thompson, @Daetalus, @romain, @rafael, @jerome