substitute the textbook-version source code for button_led2.hsp

[RollMan]

Closes #75.

Related to #73.

The commit merging this PR would be a release candidate for 2023v1.1.

[RollMan]

mandatory review items by at least two men:

• The program runs as expected (e.g., initially led being on and a button edge turns off the led).
• The textbook to have been printed out contains button_led2.hsp of exactly same as raspberry pi has.
• The textbook explains the modified button_led2.hsp without any contradictions (e.g., initial state of LED).
• In-class replacement of the material replaces correct files with correct contents ( http://ome-edu.nshimizu.com/index.php?2023%E5%B9%B4%E8%AC%9B%E7%BE%A9%E6%9C%9F%E9%96%93%E4%B8%AD%E3%81%AE%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB%E3%82%A2%E3%83%83%E3%83%97%E3%83%87%E3%83%BC%E3%83%88#b3e387c3 (internal link))

[sugasin2813]

ラズベリーパイ上で期待通りの実行が行えていることを確認しました。

[sugasin2813]

２番目、３番目について確認済み