Remove InputStream wrapper for blob download

Following NEV-254, a workaround has been done on the Connector side to handle InputStream from OkHttp returning a maximum fixed a length of 2Ko whatever the asked length (superior to 2Ko).

The target is that ARender handles it properly, following the JDK instructions (https://docs.oracle.com/en/java/javase/13/docs/api/java.base/java/io/InputStream.html#read(byte%5B%5D,int,int))