Override provider URL when initializing DNS context in case it is defined on classpath

Author: danieljohngomez

driver-core/src/main/com/mongodb/internal/dns/DefaultDnsResolver.java

@@ -146,6 +146,7 @@ public String resolveAdditionalQueryParametersFromTxtRecords(final String host)
     private static InitialDirContext createDnsDirContext() {
         Hashtable<String, String> envProps = new Hashtable<String, String>();
         envProps.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.dns.DnsContextFactory");
+        envProps.put(Context.PROVIDER_URL, "dns:");
         try {
             return new InitialDirContext(envProps);
         } catch (NamingException e) {