Fixed a filename typo preventing successful builds on Linux (where file systems are case-sensitive). (#1040)

Author: JakenVeina

src/Directory.build.targets renamed to src/Directory.Build.targets

@@ -11,7 +11,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = ".other", ".other", "{DFCC45
 		..\.gitignore = ..\.gitignore
 		..\.github\workflows\ci-build.yml = ..\.github\workflows\ci-build.yml
 		Directory.Build.props = Directory.Build.props
-		Directory.build.targets = Directory.build.targets
+		Directory.Build.targets = Directory.Build.targets
 		global.json = global.json
 		..\nuget.config = ..\nuget.config
 		..\README.md = ..\README.md