Fix: minor typo (#6088)

Fix: minor typo

Author: omahs

README.md

@@ -70,7 +70,7 @@ dnf install polkadot
 Make sure you have the support software installed from the **Build from Source** section
 below this section.
 
-If you want to install Polkadot in your PATH, you can do so with with:
+If you want to install Polkadot in your PATH, you can do so with:
 
 ```bash
 cargo install --git https://github.com/paritytech/polkadot --tag <version> polkadot --locked