Release with target platform

**Describe the bug**
When using a target platform on release, aegir does not behave like when providing it via CLI. As a consequence, it tries to run all the tests.

**To Reproduce**
Steps to reproduce the behavior:
- npx aegir test -t node
- npx aegir release -t node

**Expected behavior**
Only node tests run, instead of trying to run for all platforms, resulting in problems in repos such as `libp2p-tcp`, which does not work in the browser:

```
Command failed with exit code 1: pw-test **/*.spec.{js,ts} test/browser.{js,ts} --mode main --config /Users/vsantos/work/pl/gh/libp2p/js-libp2p-tcp/node_modules/aegir/src/config/pw-test.js --timeout=5000
Command failed with exit code 1: pw-test **/*.spec.{js,ts} test/browser.{js,ts} --mode main --config /Users/vsantos/work/pl/gh/libp2p/js-libp2p-tcp/node_modules/aegir/src/config/pw-test.js --timeout=5000
```