pg_upgrade is failed for 'plpgsql_call_handler' handler

Hi,

In one of my testing scenario, i found pg_upgrade is failed for 
'plpgsql_call_handler' handler

Steps to reproduce - ( on any supported version of PG)

Perform initdb ( ./initdb -D  d1 ;  ./initdb -D d2)

Start d1 cluster(./pg_ctl -D d1 start) , connect to postgres (./psql 
postgres)  and create this language

postgres=# CREATE TRUSTED LANGUAGE plspl_sm HANDLER plpgsql_call_handler;
CREATE LANGUAGE

stop the server (./pg_ctl -D d1 stop)

perform pg_upgrade ( ./pg_upgrade -d d1 -D d2 -b . B .)

will fail with these message

pg_restore: while PROCESSING TOC:
pg_restore: from TOC entry 825; 2612 16384 PROCEDURAL LANGUAGE plspl_sm edb
pg_restore: error: could not execute query: ERROR:  could not open 
extension control file 
"/home/edb/pg14/pg/edbpsql/share/postgresql/extension/plspl_sm.control": 
No such file or directory
Command was: CREATE OR REPLACE PROCEDURAL LANGUAGE "plspl_sm";

is this expected ?

-- 
regards,tushar
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