fix: url-form-encoded cases

Author: plaflamme

modules/openapi-generator/src/main/resources/scala-sttp4/api.mustache

@@ -31,7 +31,7 @@ class {{classname}}(baseUrl: String) {
       .cookie("{{keyParamName}}", apiKeyCookie){{/isKeyInCookie}}{{/isApiKey}}{{/authMethods}}{{#formParams.0}}{{^isMultipart}}
       .body(Map({{#formParams}}
         {{>paramFormCreation}}{{^-last}},{{/-last}}{{/formParams}}
-      )){{/isMultipart}}{{#isMultipart}}
+      ).collect { case (k, Some(v)) => k -> v }){{/isMultipart}}{{#isMultipart}}
       .multipartBody(Seq({{#formParams}}
         {{>paramMultipartCreation}}{{^-last}}, {{/-last}}{{/formParams}}
       ).flatten){{/isMultipart}}{{/formParams.0}}{{#bodyParam}}

modules/openapi-generator/src/main/resources/scala-sttp4/paramFormCreation.mustache

@@ -1 +1 @@
-"{{baseName}}" -> {{#isContainer}}ArrayValues({{{paramName}}}{{#collectionFormat}}, {{collectionFormat.toUpperCase}}{{/collectionFormat}}){{/isContainer}}{{^isContainer}}{{{paramName}}}{{/isContainer}}
+"{{baseName}}" -> {{#required}}Some({{#isContainer}}ArrayValues({{{paramName}}}{{#collectionFormat}}, {{collectionFormat.toUpperCase}}{{/collectionFormat}}){{/isContainer}}{{^isContainer}}{{{paramName}}}{{/isContainer}}){{/required}}{{^required}}{{#isContainer}}ArrayValues({{{paramName}}}{{#collectionFormat}}, {{collectionFormat.toUpperCase}}{{/collectionFormat}}){{/isContainer}}{{^isContainer}}{{{paramName}}}{{/isContainer}}{{/required}}

samples/client/petstore/scala-sttp4-circe/src/main/scala/org/openapitools/client/api/PetApi.scala

@@ -141,7 +141,7 @@ class PetApi(baseUrl: String) {
       .body(Map(
         "name" -> name,
         "status" -> status
-      ))
+      ).collect { case (k, Some(v)) => k -> v })
       .response(asString.mapWithMetadata(ResponseAs.deserializeRightWithError(_ => Right(()))))
 
   /**

samples/client/petstore/scala-sttp4/src/main/scala/org/openapitools/client/api/PetApi.scala

@@ -141,7 +141,7 @@ class PetApi(baseUrl: String) {
       .body(Map(
         "name" -> name,
         "status" -> status
-      ))
+      ).collect { case (k, Some(v)) => k -> v })
       .response(asString.mapWithMetadata(ResponseAs.deserializeRightWithError(_ => Right(()))))
 
   /**