Changed support OSes and Fixed scripts, etc

[ggtakec]

Relevant Issues/Pull Requests (if applicable)

n/a

Details

Changed in supported OS

• Ubuntu 20.04 is no longer supported
• ALPINE 3.18 is no longer supported
• ALPINE 3.21 is now supported
• Changed the base of ALPINE's Docker image to ALPINE 3.21

Fixed codes

• Fixed minor bugs in some scripts and changed the logic
• Modified the README content and changed the email address

[CLAassistant]

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