Fixes "null" strings on profile fields.

quartz/src/main/java/com/vitorpamplona/quartz/events/ContactListEvent.kt

@@ -465,6 +465,8 @@ class UserMetadata {
     fun profilePicture(): String? = picture
 
     fun cleanBlankNames() {
+        if (pronouns == "null") pronouns = null
+
         if (picture?.isNotEmpty() == true) picture = picture?.trim()
         if (nip05?.isNotEmpty() == true) nip05 = nip05?.trim()
         if (displayName?.isNotEmpty() == true) displayName = displayName?.trim()

quartz/src/main/java/com/vitorpamplona/quartz/events/MetadataEvent.kt

@@ -283,7 +283,7 @@ class MetadataEvent(
             key: String,
             value: String,
         ) {
-            if (value.isBlank()) {
+            if (value.isBlank() || value == "null") {
                 currentJson.remove(key)
             } else {
                 currentJson.put(key, value.trim())