[PDI-12190][5.2] Add null check to Hive2's HiveDriver.acceptsUrl()

Now that getActiveDriver() returns null instead of throwing an exception, we need to pull null check(s) around the calls that DriverManager makes to a driver whether it will be "selected" as a driver or not. This was done for connect() but not acceptsUrl(), this PR adds the null check to acceptsUrl
Matt,

I'm luke-warm on putting the change here because today, it's only acceptsUrl but tomorrow it may be something else. I think I'd prefer the null-check to happen in callWithActiveDriver which should throw an exception IMO. Something like:

  protected <T> T callWithActiveDriver(JDBCDriverCallable<T> callback) throws SQLException {
    Driver drv = getActiveDriver();
    if (drv != null) {
      return callback.callWithDriver(drv);
    } else {
      throw new SQLException(Messages.getString("HiveDriver.ERROR_0005", new NullPointerException());
    }
  }

Then, in acceptsURL (and possibly other methods in the class) would look more like this:

  public boolean acceptsURL(final String url) throws SQLException {
    try {
      return Boolean.TRUE.equals(callWithActiveDriver(new JDBCDriverCallable<Boolean>() {
              @Override
              public Boolean call() throws Exception {
                  return driver.acceptsURL(url);
              }
          }));
    } catch (SQLException ex) {
      // If the driver is throwing an exception, then "acceptsURL" really is false.
      return false;
    }
  }

Now, we catch both the case of an unset driver at the same time we also catch a crappy driver that doesn't support the method properly either.

Thoughts?