Fix formatting of tip section in README

Correct formatting of the tip section in README.

Author: Anmol1696

README.md

@@ -26,7 +26,7 @@ pgpm docker start
 eval "$(pgpm env)"
 ```
 
-> **Tip:** Already running Postgres? Skip the Docker step and just export your PG* vars.
+> **Tip:** Already running Postgres? Skip the Docker step and just export your PG* vars. 
 
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