wip: existence of Riemannian metrics

Mathlib.lean

@@ -3791,6 +3791,7 @@ import Mathlib.Geometry.Manifold.ContMDiffMFDeriv
 import Mathlib.Geometry.Manifold.ContMDiffMap
 import Mathlib.Geometry.Manifold.DerivationBundle
 import Mathlib.Geometry.Manifold.Diffeomorph
+import Mathlib.Geometry.Manifold.ExistsRiemannianMetric
 import Mathlib.Geometry.Manifold.GroupLieAlgebra
 import Mathlib.Geometry.Manifold.Instances.Icc
 import Mathlib.Geometry.Manifold.Instances.Real