chore(Combinatorics/SimpleGraph/Coloring/VertexColoring): rename to Vertex.lean (leanprover-community#38349)

After leanprover-community#37525 moved `Coloring.lean` to `Coloring/VertexColoring.lean`, a [Zulip](https://leanprover.zulipchat.com/#narrow/channel/252551-graph-theory/topic/Coloring.20module.20names/with/583281500) poll decided to avoid duplicating the word "Coloring", so this renames `Coloring/VertexColoring.lean` to `Coloring/Vertex.lean`.

Author: SnirBroshi

Mathlib.lean

@@ -3625,7 +3625,7 @@ public import Mathlib.Combinatorics.SimpleGraph.Circulant
 public import Mathlib.Combinatorics.SimpleGraph.Clique
 public import Mathlib.Combinatorics.SimpleGraph.Coloring.Constructions
 public import Mathlib.Combinatorics.SimpleGraph.Coloring.EdgeLabeling
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 public import Mathlib.Combinatorics.SimpleGraph.CompleteMultipartite
 public import Mathlib.Combinatorics.SimpleGraph.Connectivity.Connected
 public import Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity

Mathlib/Combinatorics/SimpleGraph/Bipartite.lean

@@ -7,7 +7,7 @@ module
 
 public import Mathlib.Algebra.Notation.Indicator
 public import Mathlib.Combinatorics.Enumerative.DoubleCounting
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 public import Mathlib.Combinatorics.SimpleGraph.Copy
 public import Mathlib.Combinatorics.SimpleGraph.DegreeSum
 

Mathlib/Combinatorics/SimpleGraph/Coloring/Constructions.lean

@@ -7,7 +7,7 @@ module
 
 public import Mathlib.Combinatorics.SimpleGraph.Bipartite
 public import Mathlib.Combinatorics.SimpleGraph.Circulant
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 public import Mathlib.Combinatorics.SimpleGraph.CompleteMultipartite
 public import Mathlib.Combinatorics.SimpleGraph.Hasse
 public import Mathlib.Data.Fin.Parity

…SimpleGraph/Coloring/VertexColoring.lean …atorics/SimpleGraph/Coloring/Vertex.leanMathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean renamed to Mathlib/Combinatorics/SimpleGraph/Coloring/Vertex.lean Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean renamed to Mathlib/Combinatorics/SimpleGraph/Coloring/Vertex.lean

@@ -5,7 +5,7 @@ Authors: John Talbot, Lian Bremner Tattersall
 -/
 module
 
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 public import Mathlib.Combinatorics.SimpleGraph.Copy
 public import Mathlib.Combinatorics.SimpleGraph.DegreeSum
 public import Mathlib.Combinatorics.SimpleGraph.Extremal.Turan

Mathlib/Combinatorics/SimpleGraph/CompleteMultipartite.lean

@@ -5,7 +5,7 @@ Authors: Arthur Paulino, Kyle Miller
 -/
 module
 
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 
 /-!
 # Graph partitions

Mathlib/Combinatorics/SimpleGraph/Partition.lean

@@ -6,7 +6,7 @@ Authors: Iván Renison
 module
 
 public import Mathlib.Combinatorics.SimpleGraph.Basic
-public import Mathlib.Combinatorics.SimpleGraph.Coloring.VertexColoring
+public import Mathlib.Combinatorics.SimpleGraph.Coloring.Vertex
 public import Mathlib.Combinatorics.SimpleGraph.Maps
 
 /-!