feat: Add script to build lock file with Docker (#70)

* Add lock.sh which uses a specified Docker image to build
  the lock file in to avoid operating system differences.
   - Nox is hard to work with in Docker, so use a manually typed
     set of shell commands over attempting to use nox inside the
     container.
   - Allow for emulation of linux/amd64 if docker runtime is other platform.
* Don't use full path in noxfile to avoid adding noise with local test
  builds.
* Add docker target to noxfile.
* Rebuild lock file using lock.sh.
* Update binder/runtime.txt to Python 3.10 to match the same runtime as the
  image that contains ROOT.
* Add build instructions to README.

README.md

@@ -25,6 +25,26 @@ To build the book after setup simply run
 make build
 ```
 
+## Build lock file
+
+To build a `pip-compile` lock file for local use `nox`
+
+```
+nox
+```
+
+To build a lock file for deployment use Docker to avoid differences between operating systems with
+
+```
+bash lock.sh
+```
+
+or
+
+```
+nox --session docker
+```
+
 ## Past tutorials
 
 * [Computational HEP Traineeship Summer School 2023](https://indico.cern.ch/event/1293313/) (2023-07-26)

binder/runtime.txt

@@ -1 +1 @@
-python-3.11
+python-3.10