No, this fortunately is not true. However it is correct that a stop for family reunification for a very specific group of people was prolonged on Thursday. The German parliament voted that people who have a residence permit for only one year (this status is called subsidiary protection) can not bring their families through a visa from a German embassy until 1st of August 2018. Please note that the procedure through a visa is mostly only relevant for refugees in Germany that have family members in non-European countries, like for example Turkey, Lebanon or Jordan. Family members in Greece can also come through the so called Dublin system and there is no stop on family reunification through the Dublin system.
According to the plans of the future German government, after the 1st of August only 1.000 people can come every months through a visa for family reunification and in addition to that also people with very special conditions like severe illnesses or other strong humanitarian reasons. Please don't mix this up with the number of people flying every months from Greece to Germany through family reunification in the Dublin system. In the Dublin procedure there is not any more a specific number of people travelling to Germany every months, but still the waiting times are long because transfers are going slow.