Start counting at postion 1

[yubiuser]

What does this PR aim to accomplish?:

A long forgotten branch adapted to v6.
awk's substr starts counting at position 1, not zero (see https://www.gnu.org/software/gawk/manual/html_node/String-Functions.html#index-substr_0028_0029-function). There is no change in output, but this is the correct way of doing things.

nanopi@nanopi:~$ git ls-remote "https://github.com/pi-hole/pi-hole" --tags development | awk '{print substr($0, 0,8);}'
300a4e22
nanopi@nanopi:~$ git ls-remote "https://github.com/pi-hole/pi-hole" --tags development | awk '{print substr($0, 1,8);}'
300a4e22

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