Remove unnecessary return statements

src/main/java/com/microsoft/sqlserver/jdbc/DDC.java

@@ -1338,7 +1338,6 @@ public void mark(int readLimit) {
         catch (IOException e) {
             // unfortunately inputstream mark does not throw an exception so we have to eat any exception from the reader here
             // likely to be a bug in the original InputStream spec.
-            return;
         }
     }
 

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerSecurityUtility.java

@@ -171,7 +171,6 @@ static void decryptSymmetricKey(CryptoMetadata md,
         assert null != cipherAlgorithm : "Cipher algorithm cannot be null in DecryptSymmetricKey";
         md.cipherAlgorithm = cipherAlgorithm;
         md.encryptionKeyInfo = encryptionkeyInfoChosen;
-        return;
     }
 
     /*

src/main/java/com/microsoft/sqlserver/jdbc/StreamTabName.java

@@ -50,6 +50,5 @@ void applyTo(Column[] columns,
         }
 
         tdsReader.reset(currentMark);
-        return;
     }
 }