Add txt to .editorconfig (#8920)

Author: sobolevn

.editorconfig

@@ -1,6 +1,6 @@
 root = true
 
-[*.{py,pyi,rst,md,yml,yaml,toml,json}]
+[*.{py,pyi,rst,md,yml,yaml,toml,json,txt}]
 trim_trailing_whitespace = true
 insert_final_newline = true
 indent_style = space