docs: add tips and tricks page

- and add first entry about python versions for building Intel FSP

Signed-off-by: AtomicFS <vojtech.vesely@9elements.com>

Author: AtomicFS

docs/src/SUMMARY.md

@@ -19,6 +19,7 @@
         - [GitHub CI](firmware-action/usage_github.md)
     - [Configuration](firmware-action/config.md)
     - [Troubleshooting](firmware-action/troubleshooting.md)
+    - [Tips and Tricks](firmware-action/tips.md)
     - [Features](firmware-action/features.md)
         - [Build Docker container on the fly](firmware-action/build_dockerfile_on_the_fly.md)
         - [Interactive debugging](firmware-action/interactive.md)

docs/src/firmware-action/tips.md

@@ -0,0 +1,11 @@
+# Tips and Tricks
+
+## Python2 for building Intel FSP
+
+Intel FSP can be build in the EDK2 containers. However the containers often have `Python3` as default.
+
+Most `EDK2` containers have `Python2` installed and contain script `switch-to-python2` (`/bin/switch-to-python2`) which will let you easily switch to `Python2` as default.
+
+```admonish tip
+To see which python version are installed and which python version is used as default, look into our [compose.yaml](https://github.com/9elements/firmware-action/blob/main/docker/compose.yaml). Specifically, look into `edk2` containers and their arguments `PYTHON_PACKAGES` (which python versions are installed) and `PYTHON_VERSION` (which python version is the default).
+```