Fix spack installation tutorial in README.md (#37)

* Fix spack installation tutorial in README.md

* Update spack installation tutorial in README.md

Author: juliusgh

README.md

@@ -64,8 +64,8 @@ Spack is a package manager designed for high-performance computing environments.
 
     ```bash
     git clone https://github.com/spack/spack.git
-    cd spack/bin
-    source ./spack
+    cd spack
+    . ./share/spack/setup-env.sh
     ```
 
 2. **Install Dependencies**: Once Spack is set up, you can install the required dependencies: