fix doctest

Author: ytdHuang

src/qobj/eigsolve.jl

@@ -467,7 +467,7 @@ vectors:
  -0.303127-0.0im   0.638838+0.0im      0.638838+0.0im  0.303127-0.0im
   0.537348+0.0im  -0.279149-0.0im      0.279149-0.0im  0.537348-0.0im
  -0.638838-0.0im  -0.303127-0.0im     -0.303127-0.0im  0.638838+0.0im
-  0.447214+0.0im   0.447214+0.0im     -0.447214-0.0im  0.447214-0.0im
+  0.447214+0.0im   0.447214+0.0im     -0.447214-0.0im  0.447214+0.0im
 
 julia> expect(H, ψ[1]) ≈ E[1]
 true