Add docs build process readme (#4772)

Signed-off-by: Peeter Piegaze <[email protected]>

docs/README.md

@@ -0,0 +1,29 @@
+# Building the Flyte docs locally
+
+## Prerequisites
+
+* `conda` (We recommend Miniconda installed with an [official installer](https://docs.conda.io/projects/miniconda/en/latest/index.html#latest-miniconda-installer-links))
+
+* [`conda-lock`](https://github.com/conda/conda-lock)
+
+
+## Set up the build environment
+
+In the `flyteorg/flyte` root directory do:
+
+```
+$ conda-lock install --name monodocs-env monodocs-environment.lock.yaml
+```
+
+This creates a new environment called `monodocs-env` with all the dependencies needed to build the docs. You can choose a different environment name if you like.
+
+
+## Building the docs
+
+In the `flyteorg/flyte` root directory make sure you have activated the `monodocs-env` (or whatever you called it) environment and do:
+
+```
+$ make docs
+```
+
+The resulting `html` files will be in `docs/_build/html`.