chg: small fix and rollback systemd.service hardening as the app is not working with this change, we should postpone this improvment to a dedicated PR

conf/systemd.service

@@ -7,41 +7,7 @@ Type=simple
 User=__APP__
 Group=__APP__
 WorkingDirectory=__INSTALL_DIR__/
-ExecStart=__INSTALL_DIR__/mautrix-signal
-
-### Depending on specificities of your service/app, you may need to tweak these
-### .. but this should be a good baseline
-# Sandboxing options to harden security
-# Details for these options: https://www.freedesktop.org/software/systemd/man/systemd.exec.html
-NoNewPrivileges=yes
-PrivateTmp=yes
-PrivateDevices=yes
-RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6 AF_NETLINK
-RestrictNamespaces=yes
-RestrictRealtime=yes
-DevicePolicy=closed
-ProtectClock=yes
-ProtectHostname=yes
-ProtectProc=invisible
-ProtectSystem=full
-ProtectControlGroups=yes
-ProtectKernelModules=yes
-ProtectKernelTunables=yes
-LockPersonality=yes
-SystemCallArchitectures=native
-SystemCallFilter=~@clock @debug @module @mount @obsolete @reboot @setuid @swap @cpu-emulation @privileged
-
-# Denying access to capabilities that should not be relevant for webapps
-# Doc: https://man7.org/linux/man-pages/man7/capabilities.7.html
-CapabilityBoundingSet=~CAP_RAWIO CAP_MKNOD
-CapabilityBoundingSet=~CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_AUDIT_WRITE
-CapabilityBoundingSet=~CAP_SYS_BOOT CAP_SYS_TIME CAP_SYS_MODULE CAP_SYS_PACCT
-CapabilityBoundingSet=~CAP_LEASE CAP_LINUX_IMMUTABLE CAP_IPC_LOCK
-CapabilityBoundingSet=~CAP_BLOCK_SUSPEND CAP_WAKE_ALARM
-CapabilityBoundingSet=~CAP_SYS_TTY_CONFIG
-CapabilityBoundingSet=~CAP_MAC_ADMIN CAP_MAC_OVERRIDE
-CapabilityBoundingSet=~CAP_NET_ADMIN CAP_NET_BROADCAST CAP_NET_RAW
-CapabilityBoundingSet=~CAP_SYS_ADMIN CAP_SYS_PTRACE CAP_SYSLOG
+ExecStart=__INSTALL_DIR__/mautrix-signal -c=__INSTALL_DIR__/config.yaml
 
 [Install]
 WantedBy=multi-user.target