Set owner of gravity output files to pihole

[yubiuser]

What does this PR aim to accomplish?:

Fixes permission issues with downloaded list and *.sha files that occurs on v6. All files in /etc/pihole should belong to pihole (See #5356). However, during pihole -up (which runs as root), the install script is called, which in turn runs gravity from /opt/pihole. All touched files will be owned by root afterwards.

In contrast, pihole -g runs gravity as pihole which causes issues at

pi-hole/gravity.sh

Line 635 in 96640ea

tr '[:upper:]' '[:lower:]' < "${src}" > "${destination}"

rw-rw----  1 pihole pihole  408  8. Okt 22:20 install.log
-rw-r--r--  1 root   root   2,9M  8. Okt 22:20 list.1.raw.githubusercontent.com.domains
-rw-r--r--  1 root   root     95  8. Okt 22:20 list.1.raw.githubusercontent.com.domains.sha1
-rw-r--r--  1 root   root   403K  8. Okt 22:20 list.2.sysctl.org.domains
-rw-r--r--  1 root   root     80  8. Okt 22:20 list.2.sysctl.org.domains.sha1
-rw-r--r--  1 root   root   913K  8. Okt 22:20 list.3.raw.githubusercontent.com.domains
-rw-r--r--  1 root   root     95  8. Okt 22:20 list.3.raw.githubusercontent.com.domains.sha1
-rw-r--r--  1 root   root   842K  8. Okt 22:20 list.4.small.oisd.nl.domains
-rw-r--r--  1 root   root     83  8. Okt 22:20 list.4.small.oisd.nl.domains.sha1
-rw-r--r--  1 pihole pihole   65  8. Okt 22:20 local.list
-rw-rw----  1 pihole pihole  241  1. Aug 23:15 logrotate
-rw-rw----  1 pihole pihole 3,0M  8. Okt 21:41 macvendor.db
drw-rw----  2 pihole pihole 4,0K  1. Aug 23:16 migration_backup
-rw-rw----  1 pihole pihole  127  1. Aug 23:15 pihole-FTL.conf.bck
-rw-rw-r--  1 pihole pihole  18M  8. Okt 22:22 pihole-FTL.db
-rw-rw----  1 pihole pihole  39K  8. Okt 22:20 pihole.toml
-rw-rw----  1 pihole pihole  347  1. Aug 23:16 setupVars.conf
-rw-rw----  1 pihole pihole  648  1. Aug 23:18 tls.crt
-rw-rw----  1 pihole pihole  936  1. Aug 23:18 tls.pem
-rw-r--r--  1 pihole pihole  385  8. Okt 22:20 versions
nanopi@nanopi:~$ pihole -g
[sudo] Passwort für nanopi: 
  [i] Neutrino emissions detected...
  [i] Storing gravity database in /etc/pihole/gravity.db
  [✓] Pulling blocklist source list into range

  [✓] Preparing new gravity database
  [✓] Creating new gravity databases
  [i] Using libz compression

  [i] Target: https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts
  [✓] Status: Retrieval successful
/opt/pihole/gravity.sh: line 635: /etc/pihole/list.1.raw.githubusercontent.com.domains: Permission denied

How does this PR accomplish the above?:

Explicitly set the invoking user to pihole in basic-install.sh when running gravity. As the gravity run is one of the last things we do, pihole should already be available.
Additionally, this requires that that /etc/pihole is writable by pihole already at that stage.

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[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/webinterface-bug/65460/5

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/docker-v6-dev-gives-weird-log-errors/65464/2