bump legacy base image and deps

[dixudx]

Fixes #4

[dixudx]

cc @chriscarnold Please help verify whether this change works. Thanks.

[chriscarnold]

Hi @dixudx, thank you for your quick response!

I tested the new Dockerfile but encountered a 500 error because mod_wsgi couldn't locate the Trac module when running as www-data. I found a solution that fixes this by:

1. Installing Trac 1.6 in a location accessible by www-data
2. Configuring mod_wsgi to use the correct Python path.

Please find my suggested fix in #6 . This resolves the 500 error and ensures Trac 1.6 works correctly when accessed through Apache. I've tested this by building and running the container locally, and confirmed that Apache can now successfully serve Trac pages without the 500 error.