Fix FSI tutorial tests

Tolerances can be loosened, since the solver uses ILU as fluid
preconditioner, which is known to be dependent on the partitioning.
Changes in partitioning yield a different solution of the linear system.
Combined with loose solver tolerances, test results change.

Author: mayrmt

tests/framework-test/tutorial_fsi_3d.head

@@ -1096,6 +1096,6 @@ SYMBOLIC_FUNCTION_OF_SPACE_TIME 10*(y-1)*(1-cos(2*t*pi/5))
 -------------------------------------------------RESULT DESCRIPTION
 STRUCTURE DIS structure NODE 80 QUANTITY dispx VALUE 5.467837e-07 TOLERANCE 1e-12
 STRUCTURE DIS structure NODE 80 QUANTITY dispy VALUE -1.177210770e-04 TOLERANCE 1e-12
-FLUID DIS fluid NODE 2000 QUANTITY pressure VALUE 7.7309079060e-03 TOLERANCE 1e-12
+FLUID DIS fluid NODE 2000 QUANTITY pressure VALUE 7.7309079060e-03 TOLERANCE 6e-12
 FLUID DIS fluid NODE 2000 QUANTITY velx VALUE 1.7064593492e-03 TOLERANCE 1e-12
 FLUID DIS fluid NODE 2000 QUANTITY vely VALUE -1.3349101929e-03 TOLERANCE 1e-12