Simplify stream chains

Author: jetersen

src/main/java/com/bettercloud/vault/api/mounts/MountPayload.java

@@ -132,11 +132,11 @@ public JsonObject toTuneJson() {
         jsonObject.addIfNotNull("description", this.description);
 
         if (this.auditNonHmacRequestKeys != null && this.auditNonHmacRequestKeys.size() > 0) {
-            jsonObject.addIfNotNull("audit_non_hmac_request_keys", this.auditNonHmacRequestKeys.stream().collect(Collectors.joining(",")));
+            jsonObject.addIfNotNull("audit_non_hmac_request_keys", String.join(",", this.auditNonHmacRequestKeys));
         }
 
         if (this.auditNonHmacResponseKeys != null && this.auditNonHmacResponseKeys.size() > 0) {
-            jsonObject.addIfNotNull("audit_non_hmac_response_keys", this.auditNonHmacResponseKeys.stream().collect(Collectors.joining(",")));
+            jsonObject.addIfNotNull("audit_non_hmac_response_keys", String.join(",", this.auditNonHmacResponseKeys));
         }
 
         return jsonObject;

src/main/java/com/bettercloud/vault/api/mounts/MountType.java

@@ -56,8 +56,7 @@ public static MountType of(final String value) {
             return null;
         }
 
-        return Arrays.asList(MountType.values())
-                .stream()
+        return Arrays.stream(MountType.values())
                 .filter(type -> type.value.equals(value))
                 .findFirst()
                 .orElse(null);