Improve aliases for Pydantic models

The pydantic models generated include field aliases for fields that use
camel case as opposed to snake case (customary in Python). The alias
definitions are compatible with python's builtin dataclasses and are
correctly detected by LSPs, however in the same models the
`populate_by_name` option is set to True. This option allows the
instantiotion using the actual field names (snake case) instead of the
defined alias (camcel case). This options is not correctly recognized by
most LSP and therefore results in two warnings per field. The first
warning states that hte snake case version of the field is not a valid
argument, and the second warning states that the camcel case version of
the argument is missing.

Exampel:

```python
class WebSessionInfo(BaseModel):
    model_config = {
        "populate_by_name": True,
    }

    session_id: str = Field(alias="sessionID")
```

The above model can be instantiated like so:
`WebSessionInfo(session_id='abc')`, however this results in two
warnings (`session_id` is not a valid argument, and `sessionID` is
missing).

Settings `validation_alias` and `serialization_alias` results in the
exact same behavior as far as validation and serialization are
concerned, however they are not standard dataclass options and are
therefore not recognized by LSPs. This removes the warnings.

Author: blubber

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPythonPydanticV1Codegen.java

@@ -908,7 +908,8 @@ private ModelsMap postProcessModelsMap(ModelsMap objs) {
 
                 // field
                 if (cp.baseName != null && !cp.baseName.equals(cp.name)) { // base name not the same as name
-                    fields.add(String.format(Locale.ROOT, "alias=\"%s\"", cp.baseName));
+                    fields.add(String.format(Locale.ROOT, "validation_alias=\"%s\"", cp.baseName));
+                    fields.add(String.format(Locale.ROOT, "serialization_alias=\"%s\"", cp.baseName));
                 }
 
                 if (!StringUtils.isEmpty(cp.description)) { // has description