Fix a file path in the core test project (yay for non-case sensitive paths on windows -.-)

Author: kMutagene

tests/CoreTests/CoreTests/CoreTests.fsproj

@@ -12,13 +12,13 @@
     <EmbeddedResource Include="..\..\..\src\Plotly.NET\plotly-2.19.1.min.js.LICENSE.txt" />
     <!--Test charts-->
     <Compile Include="HTMLCodegen\Chart2D.fs" />
-    <Compile Include="HtmlCodegen\Chart3D.fs" />
-    <Compile Include="HtmlCodegen\ChartPolar.fs" />
-    <Compile Include="HtmlCodegen\ChartMap.fs" />
-    <Compile Include="HtmlCodegen\ChartTernary.fs" />
-    <Compile Include="HtmlCodegen\ChartCarpet.fs" />
-    <Compile Include="HtmlCodegen\ChartDomain.fs" />
-    <Compile Include="HtmlCodegen\ChartSmith.fs" />
+    <Compile Include="HTMLCodegen\Chart3D.fs" />
+    <Compile Include="HTMLCodegen\ChartPolar.fs" />
+    <Compile Include="HTMLCodegen\ChartMap.fs" />
+    <Compile Include="HTMLCodegen\ChartTernary.fs" />
+    <Compile Include="HTMLCodegen\ChartCarpet.fs" />
+    <Compile Include="HTMLCodegen\ChartDomain.fs" />
+    <Compile Include="HTMLCodegen\ChartSmith.fs" />
     <!--HTMLCodegen-->
 
     <Compile Include="ChartAPIs\WithAxis.fs" />