Bump poetry from 2.1.1 to 2.1.2 (#343)

* Bump poetry from 2.1.1 to 2.1.2

Bumps [poetry](https://github.com/python-poetry/poetry) from 2.1.1 to 2.1.2.
- [Release notes](https://github.com/python-poetry/poetry/releases)
- [Changelog](https://github.com/python-poetry/poetry/blob/main/CHANGELOG.md)
- [Commits](python-poetry/poetry@2.1.1...2.1.2)

---
updated-dependencies:
- dependency-name: poetry
  dependency-version: 2.1.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

* Fix tests

* Add changelog entry

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Ed Morley <501702+edmorley@users.noreply.github.com>

Author: dependabot[bot]

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - Updated pip from 24.3.1 to 25.0.1. ([#332](https://github.com/heroku/buildpacks-python/pull/332))
+- Updated Poetry from 2.1.1 to 2.1.2. ([#343](https://github.com/heroku/buildpacks-python/pull/343))
 - Updated libcnb to 0.28.1, which includes tracing improvements/fixes. ([#344](https://github.com/heroku/buildpacks-python/pull/344))
 
 ## [0.25.0] - 2025-03-11

requirements/poetry.txt

@@ -1 +1 @@
-poetry==2.1.1
+poetry==2.1.2

tests/poetry_test.rs

@@ -234,15 +234,15 @@ fn poetry_oldest_python() {
     TestRunner::default().build(config, |context| {
         assert_contains!(
             context.pack_stdout,
-            indoc! {"
+            &formatdoc! {"
                 [Determining Python version]
                 Using Python version 3.9.0 specified in .python-version
                 
                 [Installing Python]
                 Installing Python 3.9.0
                 
                 [Installing Poetry]
-                Installing Poetry 2.1.1
+                Installing Poetry {POETRY_VERSION}
                 
                 [Installing dependencies using Poetry]
                 Creating virtual environment