Tests failing on 32 bits architecture

[lucaskanashiro]

In Debian and Ubuntu, the following tests are failing when executed in armhf (32bits):

  1) OilyPNG::Color#compose_quick should use the background color as is when a fully transparent pixel is given as foreground color
     Failure/Error: expect(compose_quick(@fully_transparent, @white)).to be(@white)

       expected #<Integer:820> => 4294967295
            got #<Integer:830> => 4294967295

       Compared using equal?, which compares object identity,
       but expected and actual are not the same object. Use
       `expect(actual).to eq(expected)` if you don't care about
       object identity in this example.
     # ./spec/color_spec.rb:24:in `block (3 levels) in <top (required)>'

  2) OilyPNG::Color#compose_quick should compose pixels correctly
     Failure/Error: expect(compose_quick(@non_opaque, @white)).to be(0x9fc2d6ff)

       expected #<Integer:840> => 2680346367
            got #<Integer:850> => 2680346367

       Compared using equal?, which compares object identity,
       but expected and actual are not the same object. Use
       `expect(actual).to eq(expected)` if you don't care about
       object identity in this example.
     # ./spec/color_spec.rb:28:in `block (3 levels) in <top (required)>'

  3) OilyPNG::Color#compose_quick should compose colors exactly the same as ChunkyPNG
     Failure/Error: expect(compose_quick(fg, bg)).to be(ChunkyPNG::Color.compose_quick(fg, bg))

       expected #<Integer:860> => 2126858483
            got #<Integer:870> => 2126858483

       Compared using equal?, which compares object identity,
       but expected and actual are not the same object. Use
       `expect(actual).to eq(expected)` if you don't care about
       object identity in this example.
     # ./spec/color_spec.rb:33:in `block (3 levels) in <top (required)>'

Debian bug as reference: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=999650

I tried to change the expect(value).to be(expected) to expect(value).to eq(expected) and the tests pass, but I am not sure if this is the right fix.