fix(python): Change template default license to Unlicense (#21514)

Author: staticdev

modules/openapi-generator/src/main/resources/python-pydantic-v1/pyproject.mustache

@@ -3,7 +3,7 @@ name = "{{{packageName}}}"
 version = "{{{packageVersion}}}"
 description = "{{{appName}}}"
 authors = ["{{infoName}}{{^infoName}}OpenAPI Generator Community{{/infoName}} <{{infoEmail}}{{^infoEmail}}team@openapitools.org{{/infoEmail}}>"]
-license = "{{{licenseInfo}}}{{^licenseInfo}}NoLicense{{/licenseInfo}}"
+license = "{{{licenseInfo}}}{{^licenseInfo}}Unlicense{{/licenseInfo}}"
 readme = "README.md"
 repository = "https://{{{gitHost}}}/{{{gitUserId}}}/{{{gitRepoId}}}"
 keywords = ["OpenAPI", "OpenAPI-Generator", "{{{appName}}}"]