3626487 - External OData call : 400 Bad Request

1. Abap to call External OData fails: 400 Bad Request 
2. ICM with trace level 2 shows, HTTP/2 is used and requet URL starting with https:// :
   
   Thr 140590563550976] HTTP request (raw) [22/31562/1]:
   [Thr 140590563550976]   GET https://XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX HTTP/1.1
   [Thr 140590563550976]   authorization: XXX
   [Thr 140590563550976]   accept: application/json;odata=verbose
   ..
   [Thr 140590563550976] HttpSubHandlerItDeactivate: handler 0: HttpLogHandler
   [Thr 140590563550976] h2: (c:19/31563) - IctHttpMessage converted to HTTP/2 HEADERS frame for stream 1
   [Thr 140590563550976] h2: (c:19/31563) - HTTP/2 sent frame HEADERS on stream 1!
   ...
   [Thr 140590563550976] h2: (c:19/31563) - HTTP/2 sent frame WINDOW_UPDATE on stream 1!
   [Thr 140590563550976] --------------------------------------
   [Thr 140590563550976] Type:    WINDOW_UPDATE (08)
   [Thr 140590563550976] Stream:    1
   [Thr 140590563550976] Length:    4
   [Thr 140590563550976] --------------------------------------
   [Thr 140590563550976] Window Size Increment:    589825
   [Thr 140590563550976] --------------------------------------
   ...
   [Thr 140590563550976] h2: (c:19/31563) - HTTP/2 received frame SETTINGS on stream 0!
   [Thr 140590563550976] --------------------------------------
   [Thr 140590563550976] Type:    SETTINGS (04)
   [Thr 140590563550976] Stream:    0
   [Thr 140590563550976] Length:    18
   [Thr 140590563550976] --------------------------------------
   [Thr 140590563550976] MAX_CONCURRENT_STREAMS (3) = 100
   [Thr 140590563550976] Unkown (16) = 2
   [Thr 140590563550976] INITIAL_WINDOW_SIZE (4) = 8388608
   [Thr 140590563550976] --------------------------------------
   [Thr 140590563550976]
   [Thr 140590563550976] h2: (c:19/31563) - Settings received!
   [Thr 140590563550976] h2: (c:19/31563) - HTTP/2 sent frame SETTINGS on stream 0!
   ...
   [Thr 140590563550976] HTTP response (raw) [22/31562/1]:
   [Thr 140590563550976]   HTTP/1.1 400 Bad Request
   [Thr 140590563550976]   content-type: text/html; charset=us-ascii
   [Thr 140590563550976]   date: Thu, 29 May 2025 10:02:36 GMT
   [Thr 140590563550976]   content-length: 311
   [Thr 140590563550976]   sap-original-protocol: h2

400 Bad Request, icm/HTTP/support_http2, icm/HTTP/client/support_http2, HTTP/2 , KBA , BC-MID-RST , REST-based Protocols , Problem