Remove duplicate url in satysfi.0.0.4

[amutake]

I've noticed that url section in opam file of satysfi.0.0.4 is duplicated.
(This git hash points to satysfi.0.0.3+dev2019.11.16)

[amutake]

before:

❯ opam install satysfi.0.0.4
[ERROR] In the opam file for satysfi.0.0.4:
          - At /Users/amutake/.opam/repo/satyrographos/packages/satysfi/satysfi.0.0.4/opam:46:0:
            Duplicate section url
        'url' has been ignored.
The following actions will be performed:
  ∗ install satysfi 0.0.4

<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
[satysfi.0.0.4] synchronised from git+https://github.com/gfngfn/SATySFi.git#69e62f66056b5644461f73c5fe8

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
∗ installed satysfi.0.0.4
Done.

after:

❯ opam install satysfi.0.0.4
The following actions will be performed:
  ∗ install satysfi 0.0.4

<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
[satysfi.0.0.4] downloaded from https://github.com/gfngfn/SATySFi/archive/v0.0.4.tar.gz

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><>  🐫
∗ installed satysfi.0.0.4
Done.

[na4zagin3]

Oops, thank you very much!!

[amutake]

Thank you for your quick response! 🙏 🙏 🙏