Fix style value for several endpoints

Author: Pijukatel

apify-api/openapi/paths/datasets/datasets@{datasetId}@items.yaml

@@ -371,7 +371,7 @@ get:
       in: query
       description: Signature used to access the items.
       required: false
-      style: simple
+      style: form
       schema:
         type: string
         example: 2wTI46Bg8qWQrV7tavlPI

apify-api/openapi/paths/key-value-stores/key-value-stores@{storeId}@keys.yaml

@@ -52,7 +52,7 @@ get:
       in: query
       description: Signature used to access the keys.
       required: false
-      style: simple
+      style: form
       schema:
         type: string
         example: 2wTI46Bg8qWQrV7tavlPI

apify-api/openapi/paths/key-value-stores/key-value-stores@{storeId}@records@{recordKey}.yaml

@@ -36,7 +36,7 @@ get:
       in: query
       description: Signature used to access the record.
       required: false
-      style: simple
+      style: form
       schema:
         type: string
         example: 2wTI46Bg8qWQrV7tavlPI