synthio: enable additional LFO test cases

Author: jepler

tests/circuitpython/synthlfo.py

@@ -10,9 +10,9 @@
 lfos = [
     LFO(bend_out, once=True, rate=4),
     LFO(bend_in, once=True, rate=2.5, scale=2),
-    LFO(triangle, rate=3)
-    #    LFO(bend_in, interpolate=False, rate=5),
-    #    LFO(bend_in, interpolate=True, rate=5),
+    LFO(triangle, rate=3),
+    LFO(bend_in, interpolate=False, rate=5),
+    LFO(bend_in, interpolate=True, rate=5),
 ]
 lfos[2].rate = lfos[1]
 lfos[2].offset = lfos[0]