3.0.0a4

What's Changed

• Fix import errors in tips and tricks by @jonhealy1 in #710
• add tests for FieldsExtension impact on validation by @vincentsarago in #708
• #711 changed default filter language by @captaincoordinates in #712
• Remove the Filter Extension dependency from Aggregation Extension requests by @jamesfisher-gis in #716
• remove middleware stack building to avoid conflict with exception handler by @vincentsarago in #721
• raise RuntimeError if middleware stack has already been created when initialiazing StacApi by @vincentsarago in #722
• Release/v3.0.0a4 by @vincentsarago in #723

Full Changelog: 3.0.0a3...3.0.0a4