🐛 — Fix timezone mess

I had one operation which date was at midnight, but with a +0200
timezone. The looking for similar operations was made with this date but
in GMT time, two hours before, so Kresus was looking in the previous
day. The result was that the last operation was always duplicated, each
day I had to merge it.

With this commit, I remove the change of timezone in the dates used for
looking for similar operations.
1 job for fix-tz-mess in 5 minutes and 33 seconds (queued for 1 second)
Status Job ID Name Coverage
passed ci #1370247