message: fix: use dashboard id for stable cache key
diff: @@ -156,7 +156,7 @@ class Dashboard( # pylint: disable=too-many-instance-attributes
  ]
  def __repr__(self) -> str:
  - return f"Dashboard<{self.slug or self.id}>"
  + return f"Dashboard<{self.id or self.slug}>"
  @property
  def table_names(self) -> str:
  @@ -253,7 +253,7 @@ class Dashboard( # pylint: disable=too-many-instance-attributes
  @cache.memoize(
  # manage cache version manually
  - make_name=lambda fname: f"{fname}-v2",
  + make_name=lambda fname: f"{fname}-v2.1",
  timeout=config["DASHBOARD_CACHE_TIMEOUT"],
  unless=lambda: not is_feature_enabled("DASHBOARD_CACHE"),
  )
  