jibri: fix variable names

Fixes: https://github.com/jitsi/docker-jitsi-meet/issues/1607

jibri/rootfs/defaults/jibri.conf

@@ -4,9 +4,9 @@
 {{ $JIBRI_RECORDING_RESOLUTION := .Env.JIBRI_RECORDING_RESOLUTION | default "1280x720" -}}
 {{ $JIBRI_RECORDING_VIDEO_ENCODE_PRESET := .Env.JIBRI_RECORDING_VIDEO_ENCODE_PRESET | default "veryfast" -}}
 {{ $JIBRI_RECORDING_CONSTANT_RATE_FACTOR := .Env.JIBRI_RECORDING_CONSTANT_RATE_FACTOR | default 25 -}}
-{{ $JIBRI_RECORDING_FRAMERATE := .Env.$JIBRI_RECORDING_FRAMERATE | default 30 -}}
-{{ $JIBRI_RECORDING_QUEUE_SIZE := .Env.$JIBRI_RECORDING_QUEUE_SIZE | default 4096 -}}
-{{ $JIBRI_RECORDING_STREAMING_MAX_BITRATE := .Env.$JIBRI_RECORDING_STREAMING_MAX_BITRATE | default 2976 -}}
+{{ $JIBRI_RECORDING_FRAMERATE := .Env.JIBRI_RECORDING_FRAMERATE | default 30 -}}
+{{ $JIBRI_RECORDING_QUEUE_SIZE := .Env.JIBRI_RECORDING_QUEUE_SIZE | default 4096 -}}
+{{ $JIBRI_RECORDING_STREAMING_MAX_BITRATE := .Env.JIBRI_RECORDING_STREAMING_MAX_BITRATE | default 2976 -}}
 {{ $JIBRI_BREWERY_MUC := .Env.JIBRI_BREWERY_MUC | default "jibribrewery" -}}
 {{ $JIBRI_SINGLE_USE_MODE := .Env.JIBRI_SINGLE_USE_MODE | default "false" -}}
 {{ $XMPP_AUTH_DOMAIN := .Env.XMPP_AUTH_DOMAIN | default "auth.meet.jitsi" -}}