Update build-constraints.yaml

Added Vivian McPhail's projects to `build-constraints.yaml`.

build-constraints.yaml

@@ -831,6 +831,16 @@ packages:
     "Andres Löh <andres@well-typed.com> @kosmikus":
         - generics-sop
 
+    "Vivian McPhail <haskell.vivian.mcphail@gmail.com>":
+        - hmatrix-gsl-stats
+        - hstatistics
+        - hsignal
+        - plot
+        - plot-gtk
+        - plot-gtk3
+        - vector-buffer
+        - hmatrix-repa
+        
     "Stackage upper bounds":
         # GHC 7.8 uppdate bound
         - haddock-api < 2.16