Current main-branch version of buildpack isn't deployable

[arthfl]

Ahoy,

The current main branch (7b37993) seems to have a bug that lets a very simple app deployment fail currently:

2025-12-16T10:14:02.29+0100 [STG/0] OUT -----> Finalizing PHP
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Copied rewrite binary to .bp/bin
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Loading default options from embedded config
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Set PHP_DEFAULT = 8.1.32 from manifest
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Set PHP_81_LATEST = 8.1.32
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Set PHP_82_LATEST = 8.2.28
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Set PHP_83_LATEST = 8.3.21
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Using web server: httpd (from options.json)
   2025-12-16T10:14:02.29+0100 [STG/0] OUT Created start script for httpd
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Created pre-start wrapper script
   2025-12-16T10:14:02.29+0100 [STG/0] OUT DEBUG: Created PHP runtime directory: /tmp/contents667600700/deps/0/php/var/run
   2025-12-16T10:14:02.29+0100 [STG/0] OUT PHP buildpack finalize phase complete
   2025-12-16T10:14:05.17+0100 [STG/0] ERR Failed to build droplet release: buildpack's release output invalid: yaml: line 4: mapping values are not allowed in this context
   2025-12-16T10:14:05.18+0100 [STG/0] OUT Exit status 224
   2025-12-16T10:14:05.69+0100 [STG/0] OUT Cell c2ce894c-7146-4119-8f66-065da745909f stopping instance e2f5e0b4-9f57-4b0c-b9a1-84a86c076b35
   2025-12-16T10:14:05.69+0100 [STG/0] OUT Cell c2ce894c-7146-4119-8f66-065da745909f destroying container for instance e2f5e0b4-9f57-4b0c-b9a1-84a86c076b35
   2025-12-16T10:14:05.75+0100 [API/0] ERR Failed to stage build: staging failed

This is from a minimal hello-world-ish sample app we deploy daily to test our (Dynatrace) buildpack integration.
The manifest looks like

---
applications:
  - name: php-sample
    memory: 256M
    instances: 1
    buildpacks:
        - https://github.com/cloudfoundry/php-buildpack.git
    env:
      BP_DEBUG: true

This is happening since November 21st 2025 constantly.

The latest stable release of the php-buildpack works just fine.