add_repo Bash script needs Bash Shebang to run straight from the shell

[Gitsarry]

OS: Debian Bullseye

According to
https://i2pd.readthedocs.io/en/latest/user-guide/install/ -> Debian section
and
https://repo.i2pd.xyz/.help/readme.html

one should download and run the script "add_repo" with the Bash interpreter, using the following command:

$ wget -q -O - https://repo.i2pd.xyz/.help/add_repo | sudo bash -s -

(note the "bash" command here)

Since I like to see a script before I download it from the internet and run it as root, I downloaded it manually with just

$ wget -q https://repo.i2pd.xyz/.help/add_repo
reviewed it, made it executable with chmod +x add_repo and then did sudo ./add_repo
But that exits with the error:

./add_repo: 3: [[: not found
./add_repo: 9: source: not found
./add_repo: 11: function: not found
./add_repo: 30: [[: not found
./add_repo: 30: : Permission denied
./add_repo: 62: [[: not found
./add_repo: 66: Syntax error: "}" unexpected

That's because the add_repo script has the #!/bin/sh shebang, and that symlinks to /bin/dash on Debian Bullseye and Dash does not understand the if clause with double brackets like if [[ $EUID -ne 0 ]]; then.

Since Bash is mandatory and documented, I would suggest to set the shebang in add_repo to #/bin/bash accordingly.

Workaround would be to run sudo bash ./add_repo but that's unnecessary complicated and I do not see a reason why not to define the proper Shebang in the script itself.

I did not find a github repo for https://repo.i2pd.xyz/.help/add_repo, if I had, I would have created a pull request already.