Merge branch 'no_null_values' into 'main'

enh: avoid null values dumping when apply md

See merge request umr-tetis/stac/extensions/pydantic-pystac-extensions!6

pydantic_pystac_extensions/__init__.py

@@ -2,4 +2,4 @@
 
 from .core import create_extension_cls, BaseExtensionModel  # noqa
 
-__version__ = "0.1.5"
+__version__ = "0.1.6"

pydantic_pystac_extensions/core.py

@@ -72,7 +72,8 @@ def create_extension_cls(model_cls: BaseModel, schema_uri: str) -> PropertiesExt
             md = md or model_cls(**kwargs)
             for key, value in md.model_dump(exclude_unset=True).items():
                 alias = model_cls.model_fields[key].alias or key
-                self._set_property(alias, value, pop_if_none=False)
+                if value:
+                    self._set_property(alias, value, pop_if_none=False)
 
         @classmethod
         def get_schema_uri(cls) -> str: