Clean up lint findings exposed by black 26 reformat

- Ignore E704 in flake8: black 26 collapses abstract method stubs
  (def foo(): ...) onto one line; E704 conflicts with that style.
- Drop unused imports RecommendationValue and NAN_LITERAL in
  formatters/table.py.
- Replace unnecessary f-string with plain triple-quoted string in
  strategies/simple.py (F541).

Author: claude

.flake8

@@ -12,4 +12,4 @@ exclude = .git,
     .mypy_cache,
     src/robusta/integrations/kubernetes/autogenerated,
     src/robusta/integrations/kubernetes/custom_models.py
-ignore = E501, W503, E203
+ignore = E501, W503, E203, E704

robusta_krr/formatters/table.py

@@ -5,11 +5,9 @@
 
 from robusta_krr.core.abstract import formatters
 from robusta_krr.core.models.allocations import (
-    RecommendationValue,
     format_recommendation_value,
     format_diff,
     NONE_LITERAL,
-    NAN_LITERAL,
 )
 from robusta_krr.core.models.result import ResourceScan, ResourceType, Result
 from robusta_krr.core.models.config import settings

robusta_krr/strategies/simple.py

@@ -101,7 +101,7 @@ def description(self):
             """)
 
         if not self.settings.allow_hpa:
-            s += "\n" + textwrap.dedent(f"""\
+            s += "\n" + textwrap.dedent("""\
                 This strategy does not work with objects with HPA defined (Horizontal Pod Autoscaler).
                 If HPA is defined for CPU or Memory, the strategy will return "?" for that resource.
                 You can override this behaviour by passing the --allow-hpa flag