arrow

GH-45076: [CI][Packaging][Python] Simplify dev/tasks/python-wheels/github.linux.yml (#45077)

### Rationale for this change

We can use GitHub Actions' standard features not Jinja2 features to generate test image names.

### What changes are included in this PR?

Use `GITHUB_ENV` instead of Jinja2.

### Are these changes tested?

Yes.

### Are there any user-facing changes?

No.

* GitHub Issue: https://github.com/apache/arrow/issues/45076

Authored-by: Sutou Kouhei <kou@clear-code.com>
Signed-off-by: Raúl Cumplido <raulcumplido@gmail.com>