fix: add ./ prefix to lint task path for CI compatibility

The lint task was failing in GitHub Actions because the Python script path
was not being resolved correctly. Adding ./ prefix matches the pattern used
by other Python tasks (sort, merge, next) and ensures the path is resolved
relative to the project root in the pixi environment.

Author: JesperDramsch

pixi.toml

@@ -25,7 +25,7 @@ test = "pytest tests/ -v"
 test-cov = "pytest tests/ -v --cov=utils --cov-report=term-missing"
 test-fast = "pytest tests/ -v -x"
 pre = "pre-commit run --all-files"
-lint = "python utils/conferences/linters/validate.py"
+lint = "python ./utils/conferences/linters/validate.py"
 
 [dependencies]
 python = ">=3.10,<3.12"