Fix tox-docker builds after #29941

[mkoeppe]

src/VERSION.txt is needed in the Docker container after #29941.

This fixes the failures seen in https://github.com/sagemath/sage/actions/runs/2483481917
and also reported in pypa/setuptools#3389

CC: @dimpase @kliem @kiwifb

Component: porting

Author: Matthias Koeppe

Branch/Commit: 58d62f4

Reviewer: François Bissey

Issue created by migration from https://trac.sagemath.org/ticket/34017

[mkoeppe]

Branch: u/mkoeppe/fix_tox_docker_builds_after__29941

[mkoeppe]

New commits:

58d62f4

build/bin/write-dockerfile.sh: ADD src/VERSION.txt

[mkoeppe]

Commit: 58d62f4

[mkoeppe]

comment:3

Let's get this in please

[dimpase]

comment:4

how does one test this? (I guess a box
with docker is needed)

[mkoeppe]

comment:5

The branch fixes what runs on GH Actions

[mkoeppe]

comment:6

Running (with some other tickets) for example in https://github.com/mkoeppe/sage/runs/7056478381

[kiwifb]

comment:8

If it fixes the failures mentioned in the ticket in CI, I think that should count as automatically reviewed. The proof is in that pudding.

[kiwifb]

Reviewer: François Bissey

[mkoeppe]

comment:9

I'm interpreting this as a positive review, thanks

[kiwifb]

comment:10

Yes, I thought I had ticked that box :)

[vbraun]

Changed branch from u/mkoeppe/fix_tox_docker_builds_after__29941 to 58d62f4