test: eachindex for arbitrary number of arguments (#51941)

added test cases for `eachindex` to cover arbitrary number of arguments

![image](https://github.com/JuliaLang/julia/assets/49565677/fa39cb8c-2523-40c0-90f3-e3f90f54397e)

Author: PraneethJain

test/arrayops.jl

@@ -2128,6 +2128,8 @@ R = CartesianIndices((3,0))
     @test @inferred(eachindex(Base.IndexLinear(), a, b)) == 1:4
     @test @inferred(eachindex(a, b)) == CartesianIndices((2,2))
     @test @inferred(eachindex(a, a)) == 1:4
+    @test @inferred(eachindex(a, a, a)) == 1:4
+    @test @inferred(eachindex(a, a, b)) == CartesianIndices((2,2))
     @test_throws DimensionMismatch eachindex(a, rand(3,3))
     @test_throws DimensionMismatch eachindex(b, rand(3,3))
 end