Improve error message for wrong secrets / environment config

[6543]

also address https://github.com/woodpecker-ci/woodpecker/issues/4306

Before

After

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 91.66667% with 2 lines in your changes missing coverage. Please review.

Project coverage is 27.37%. Comparing base (a1193f0) to head (26e8f2f). Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
pipeline/frontend/yaml/types/base/deprecations.go	91.66%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #4359 +/- ## ========================================== + Coverage 27.32% 27.37% +0.05% ========================================== Files 379 380 +1 Lines 27757 27781 +24 ========================================== + Hits 7584 7606 +22 - Misses 19488 19490 +2 Partials 685 685 ```

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[xoxys]

Shouldn't it go to the changelog? Or why have you set the skip-changelog label?

[6543]

this not as it just improves an already existing error message ... folowups in this area do

[woodpecker-bot]

Tearing down https://woodpecker-ci-woodpecker-pr-4359.surge.sh