required version of GLIB_C blocks use of beibootctl on older OS versions (Amazon Linux 2)

[RiccardoBoettcher]

beibootctl version: 1.4.0 OS: Amazon Linux 2

The dependencies compiled into the binary can't be fulfilled. See attached logs. This makes the tool unusable on older OS versions like Amazon Linux 2 (AL2). The latter is quite frequently used in AWS and should be supported. Other kubernetes tools like (kubectl, helm, k9s) work with Amazon Linux 2 without problems.

More information for glibc on AL2: https://repost.aws/questions/QUrXOioL46RcCnFGyELJWKLw/glibc-2-27-on-amazon-linux-2

If possible lower the dependencies on external libraries.

--- logs ---

$beibootctl 
beibootctl: /lib64/libm.so.6: version `GLIBC_2.29' not found (required by beibootctl)
beibootctl: /lib64/libc.so.6: version `GLIBC_2.28' not found (required by beibootctl)
beibootctl: /lib64/libc.so.6: version `GLIBC_2.29' not found (required by beibootctl)

$ldd (GNU libc) 2.26
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