Use same notation style for sparse and Matrix in SparseArrays docs (J…

…uliaLang#37543)

stdlib/SparseArrays/docs/src/index.md

@@ -193,7 +193,7 @@ section of the standard library reference.
 | Sparse | Dense | Description |
 |:-------------------------- |:---------------------- |:--------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | [`spzeros(m,n)`](@ref) | [`zeros(m,n)`](@ref) | Creates a *m*-by-*n* matrix of zeros. ([`spzeros(m,n)`](@ref) is empty.) |
-| [`sparse(I, n, n)`](@ref) | [`Matrix(I,n,n)`](@ref)| Creates a *n*-by-*n* identity matrix. |
+| [`sparse(I,n,n)`](@ref) | [`Matrix(I,n,n)`](@ref)| Creates a *n*-by-*n* identity matrix. |
 | [`sparse(A)`](@ref) | [`Array(S)`](@ref) | Interconverts between dense and sparse formats. |
 | [`sprand(m,n,d)`](@ref) | [`rand(m,n)`](@ref) | Creates a *m*-by-*n* random matrix (of density *d*) with iid non-zero elements distributed uniformly on the half-open interval ``[0, 1)``. |
 | [`sprandn(m,n,d)`](@ref) | [`randn(m,n)`](@ref) | Creates a *m*-by-*n* random matrix (of density *d*) with iid non-zero elements distributed according to the standard normal (Gaussian) distribution. |