.editorconfig: treat only extension-less files as shell scripts

Using the workaround from editorconfig/editorconfig#401 (comment)

Author: generalmimon

.editorconfig

@@ -9,21 +9,23 @@ trim_trailing_whitespace = true
 # We usually want to indent using spaces
 indent_style = space
 
-[*.{cpp,h}]
-indent_size = 4
-
-[*.yml]
-indent_size = 2
-
-# Assume that most of the files in the .build/ directory are shell scripts...
+# Files in the .build/ directory without a file extension are shell scripts
 [.build/*]
 indent_size = 4
 indent_style = tab
 
-# ... but use 4-space indentation for PowerShell scripts
+[.build/*.*]
+indent_size = unset
+indent_style = space
+
 [*.ps1]
 indent_size = 4
-indent_style = space
+
+[*.yml]
+indent_size = 2
+
+[*.{cpp,h}]
+indent_size = 4
 
 [{CMakeLists.txt,*.cmake}]
 indent_size = 4