README.md: add how to load Haskell REPL

Anton-Latukha · Anton-Latukha · commit cc468af340f8 · 2020-09-30T17:00:52.000+03:00
diff --git a/README.md b/README.md
@@ -59,6 +59,11 @@ cabal v2-configure
 cabal v2-build
 ```
 
+3. Loading the project into `ghci` REPL:
+```
+cabal v2-repl
+```
+
 3. Testing:
 
 * Default suite:
