update FAQ about 'fire: command not found' error

Author: tomeichlersmith

src/developing/faq.md

@@ -3,22 +3,14 @@ Frequent issues and potholes that new collaborators run into while starting thei
 
 ~~~admonish question collapsible=true title="fire: command not found"
 This error can arise pretty easily but luckily it has a pretty easily solution.
-The [current entrypoint script](https://github.com/LDMX-Software/docker/blob/main/entry.sh)
-for the development environment[^1] (`ldmx/dev` images)
-assume that ldmx-sw is installed into the path at `${LDMX_BASE}/ldmx-sw/install`, so
-if any of the following are true, you will see the `fire: command not found` error.
-- `LDMX_BASE` is not the full path to the directory containing ldmx-sw.
-- The directory with the ldmx-sw source is not named `ldmx-sw`.
-- The user configured ldmx-sw to be installed somewhere else with `-DCMAKE_INSTALL_PREFIX=...`.
+The environment in the container assumes that ldmx-sw installed into the path
+at `path/to/ldmx-sw/install`, so if ldmx-sw is installed somewhere else
+(e.g. with `-DCMAKE_INSTALL_PREFIX=...`), then you will see the `fire: command not found`
+error.
 
 The `ldmx/pro` images (short for "production") already have a copy of ldmx-sw compiled
 and installed into them and so they do not have this path resolution requirement in order
 to access the `fire` command.
-
-[^1]: I say "current" because there [is some discussion](https://github.com/LDMX-Software/ldmx-sw/issues/1232)
-about re-designing the container interaction to avoid such heavy reliance on the entrypoint in the image.
-Avoiding this reliance would make it easier for users to switch between images, but it would
-require us to learn a slightly new interaction workflow.
 ~~~
 
 ~~~admonish question collapsible=true title="Compile error: ap_fixed.h: No such file or directory."