Remove the dnf_manager exceptions related to selection resolving

The exceptions are not actually raised anywhere and the report is now
constructed right away in the resolve_selection method, so it doesn't
make sense to raise these and catch elsewhere to add the messages to
the report as it was done previously.

pyanaconda/modules/payloads/payload/dnf/dnf_manager.py

@@ -88,18 +88,6 @@ class MetadataError(DNFManagerError):
     """Metadata couldn't be loaded."""
 
 
-class MissingSpecsError(DNFManagerError):
-    """Some packages, groups or modules are missing."""
-
-
-class BrokenSpecsError(DNFManagerError):
-    """Some packages, groups or modules are broken."""
-
-
-class InvalidSelectionError(DNFManagerError):
-    """The software selection couldn't be resolved."""
-
-
 class DNFManager:
     """The abstraction of the DNF base."""
 
@@ -597,8 +585,6 @@ def apply_specs(self, include_list, exclude_list):
 
         :param include_list: a list of specs for inclusion
         :param exclude_list: a list of specs for exclusion
-        :raise MissingSpecsError: if there are missing specs
-        :raise BrokenSpecsError: if there are broken specs
         """
         log.info("Including specs: %s", include_list)
         for spec in include_list:
@@ -609,10 +595,7 @@ def apply_specs(self, include_list, exclude_list):
             self._goal.add_remove(spec)
 
     def resolve_selection(self):
-        """Resolve the software selection.
-
-        :raise InvalidSelectionError: if the selection cannot be resolved
-        """
+        """Resolve the software selection."""
         report = ValidationReport()
 
         log.debug("Resolving the software selection.")