caldb unversioned -- potentially cause issues later in time?

[falkben]

in our dockerfile and instructions to users, the link to install caldb and caldb data files is to just the latest version. this is because I cannot find a versioned file to point to instead.

this caused errors when the caldbinit.sh file moved inside the caldb installation, causing our docker builds to fail until i figured out what was going on.

Locations where we reference the latest version URL:

• https://github.com/spacetelescope/DRESSCode/blob/main/docs/install.md?plain=1#L51
• https://github.com/spacetelescope/DRESSCode/blob/main/Docker/heasoft-caldb-wcstools.dockerfile#L29
• https://github.com/spacetelescope/DRESSCode/blob/main/Docker/heasoft-caldb-wcstools.dockerfile#L32

Unfortunately, without a versioned URL to the caldb software, I'm not sure we can fix this. We could consider caldb to be a database, and we are just always pointing to that database.

Related to: #70