Skip NetteDatabaseTest when database connection unavailable

[ohmyfelix]

This change adds a database connectivity check to the NetteDatabaseTest to gracefully skip the test suite when the database is not available, rather than failing with connection errors.

Key changes:

• Added use Tester\Environment; import to enable test skipping functionality
• Added a try-catch block that attempts to connect to the test database (MySQL on localhost:13306)
• If the connection fails with a ConnectionException, the test suite is skipped with an informative message
• This allows the test suite to run in environments where the database may not be available without causing test failures

Implementation details:

• The connection check uses the same credentials and database configuration that the tests would use
• The skip is triggered before the test class is defined, preventing any database-dependent tests from running
• This is a common pattern for integration tests that depend on external services

https://claude.ai/code/session_01A8V5dTVDGP1CJTsjzfmosR