CompatHelper: bump compat for "BandedMatrices" to "0.15" (#11)

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Author: github-actions[bot]

Project.toml

@@ -35,7 +35,7 @@ ApproxFunBase = "0.3"
 ApproxFunFourier = "0.2"
 ApproxFunOrthogonalPolynomials = "0.3"
 ArrayLayouts = "0.1"
-BandedMatrices = "0.14"
+BandedMatrices = "0.14, 0.15"
 BlockArrays = "0.11"
 BlockBandedMatrices = "0.7"
 DomainSets = "0.1"