CompatHelper: bump compat for "IntervalSets" to "0.6" (#69)

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

Project.toml

@@ -30,7 +30,7 @@ FFTW = "1.1"
 FastGaussQuadrature = "0.4"
 FastTransforms = "0.12, 0.13"
 FillArrays = "0.11, 0.12, 0.13"
-IntervalSets = "0.5"
+IntervalSets = "0.5, 0.6"
 Reexport = "0.2, 1"
 SpecialFunctions = "0.10, 1.0, 2"
 julia = "1.5"