BUG #18635: " $libdir/adminpack could not be loaded" error with pg_upgrade to PostgreSQL17

The following bug has been logged on the website:

Bug reference:      18635
Logged by:          xu bing
Email address:      bing.xu.uh@fujifilm.com
PostgreSQL version: 17.0
Operating system:   windows server 2019 Datacenter
Description:

■Describe the bug
While upgrading a PSQL 14. 3　instance to PSQL 17 I have an error with
pg_upgrade, saying that the libraray "$libdir/adminpack" can not be
loaded.

■To Reproduce
1.Install PostgreSQL 17

2.Stop PostgreSQL Service
　　net stop postgresql-x64-14

3.Run pg_upgrade

"C:\Program Files\PostgreSQL\17\bin\pg_upgrade.exe" -U postgres -d
"C:\Program Files\PostgreSQL\14\data" -D "C:\Program
Files\PostgreSQL\17\data" -b "C:\Program Files\PostgreSQL\14\bin" -B
"C:\Program Files\PostgreSQL\17\bin"

4.Output

整合性チェックを実行しています。
-----------------------------
Checking cluster versions                                     ok
Checking database user is the install user                    ok
Checking database connection settings                         ok
Checking for prepared transactions                            ok
Checking for contrib/isn with bigint-passing mismatch         ok
Checking data type usage                                      ok
Creating dump of global objects                               ok
Creating dump of database schemas                             
                                                              ok
Checking for presence of required libraries                   致命的
このクラスタでは、移行先の環境にはないロード可能ライブラリを参照しています。
これらのライブラリを移行先の環境に追加するか、もしくは移行元の環境から
それらを使っている関数を削除してください。 問題のライブラリの一覧は、
以下のファイルに入っています:
    C:/Program
Files/PostgreSQL/17/data/pg_upgrade_output.d/20240927T110225.604/loadable_libraries.txt

loadable_libraries.txt
ライブラリ"$libdir/adminpack"をロードできませんでした: ERROR:
繝輔ぃ繧､繝ｫ"$libdir/adminpack"縺ｫ繧｢繧ｯ繧ｻ繧ｹ縺ｧ縺阪∪縺帙ｓ縺ｧ縺励◆: No such file or
directory
データベース: postgres

■Additional infos
  I saw that Release Notes said that  adminpack contrib extension has been
Removed, but why is it still used in pg_upgrade of PostgreSQL17.
  Also please tell me the solution.

-------------------------------------
●Remove adminpack contrib extension (Daniel Gustafsson) §
　This was used by now end-of-life pgAdmin III.

https://www.postgresql.org/docs/release/17.0/
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