Apply suggestions from code review

Co-authored-by: Guillaume Dalle <22795598+gdalle@users.noreply.github.com>

Author: amontoison

src/check.jl

@@ -130,7 +130,7 @@ A bipartition of the rows and columns of a matrix `A` is _structurally biorthogo
 1. the group containing the column `A[:, j]` has no other column with a nonzero in row `i`
 2. the group containing the row `A[i, :]` has no other row with a nonzero in column `j`
 
-It is equivalent to an __star bicoloring__.
+It is equivalent to a __star bicoloring__.
 
 !!! warning
     This function is not coded with efficiency in mind, it is designed for small-scale tests.

test/check.jl

@@ -233,9 +233,9 @@ end
 
     # success
 
-    substitutable_columns(A1, B1, [1, 2, 2, 2, 2])
-    substitutable_columns(A2, B2, [1, 2, 3, 1, 2])
-    substitutable_columns(A3, B3, [1, 2, 3, 4, 0])
+    @test substitutable_columns(A1, B1, [1, 2, 2, 2, 2])
+    @test substitutable_columns(A2, B2, [1, 2, 3, 1, 2])
+    @test substitutable_columns(A3, B3, [1, 2, 3, 4, 0])
 
     # failure
 
@@ -298,7 +298,7 @@ end
 
     # success
 
-    substitutable_bidirectional(A, B, [1, 0, 0], [0, 1, 1])
+    @test substitutable_bidirectional(A, B, [1, 0, 0], [0, 1, 1])
 
     # failure