Add docs note about authenticated queries

Author: juanmcloaiza

docs/eso/eso.rst

@@ -103,6 +103,27 @@ interaction with the ESO archive.
     INFO: Downloading file 1/1 https://dataportal.eso.org/dataPortal/file/ADP.2023-03-02T01:01:24.355
     ERROR: Access denied to https://dataportal.eso.org/dataPortal/file/ADP.2023-03-02T01:01:24.355
 
+.. note::
+    Even after logging with `Eso.login()`, TAP queries are not authenticated by default. To issue
+    authenticated queries, the keyword argument `authenticated` must be set to `True` explicitly in
+    the query functions. For example:
+
+    .. doctest-skip::
+
+        eso = Eso()
+        eso.ROW_LIMIT = None
+        eso.login(username="ICONDOR")
+
+        # Some files are missing without `authenticated=True`
+        files_tbl = eso.query_instrument("nirps")
+
+        # Get all files to which the authenticated user has access
+        files_tbl = eso.query_instrument("nirps", authenticated=True)
+
+    Review your queries carefully and update them accordingly to ensure you are retrieving
+    all your expected results. If you don't stricly need to run an authenticated query, use 
+    the default `authenticated=False`, since it will retrieve your results much faster.
+
 Automatic password
 ------------------