add instruction for building the kernels

Author: MartinSchobben

README.md

@@ -75,10 +75,9 @@ If you are interested in running this material locally on your computer, you wil
    ```bash
    cd eo-datascience-cookbook
    ```
-1. Create and activate your conda environment from the `environment.yml` file
+1. Create Jupyter kernels
    ```bash
-   conda env create -f environment.yml
-   conda activate eo-datascience-cookbook
+   make kernel
    ```
 1. Move into the `notebooks` directory and start up Jupyterlab
    ```bash