docs: drop not about wildcards

Author: tos-kamiya

README.md

@@ -188,22 +188,6 @@ $ dendro_text -c *.txt --prep 'sed s/c//g'
 
 ## Note
 
-### Wildcard on Windows
-
-In Windows, wildcard expansion is supposed to be done on the command side, but `dendro_text` itself does not have wildcard expansion capability.
-
-If you want to specify files with wildcards in a windows environment, use Powershell's command substitution feature. For example, instead of the following command line:
-
-```sh
-dendro_text *.txt
-```
-
-Use the following:
-
-```sh
-dendro_text $(ls *.txt)
-```
-
 ### The default tokenization
 
 The default tokenization (extracting words from the text) method is to split text at the point where the type of letter changes.