IPFS uploader: dialyzer fixes

lib/pleroma/uploaders/ipfs.ex:43:no_return
Function put_file/1 has no local return.
________________________________________________________________________________
lib/pleroma/uploaders/ipfs.ex:49:call
The function call will not succeed.

Pleroma.HTTP.post(
  binary(),
  _mp :: %Tesla.Multipart{
    :boundary => binary(),
    :content_type_params => [binary()],
    :parts => [
      %Tesla.Multipart.Part{
        :body => binary(),
        :dispositions => [any()],
        :headers => [any()]
      },
      ...
    ]
  },
  [],
  [{:params, [{:"cid-version", <<49>>}]}]
)

will never return since the success typing is:
(binary(), binary(), [{binary(), binary()}], Keyword.t()) ::
  {:error, _}
  | {:ok,
     %Tesla.Env{
       :__client__ => %Tesla.Client{
         :adapter => nil | {_, _} | {_, _, _},
         :fun => _,
         :post => [any()],
         :pre => [any()]
       },
       :__module__ => atom(),
       :body => _,
       :headers => [{_, _}],
       :method => :delete | :get | :head | :options | :patch | :post | :put | :trace,
       :opts => [{_, _}],
       :query => [{_, _}],
       :status => nil | integer(),
       :url => binary()
     }}

and the contract is
(Pleroma.HTTP.Request.url(), String.t(), Pleroma.HTTP.Request.headers(), :elixir.keyword()) ::
  {:ok, Tesla.Env.t()} | {:error, any()}

config/config.exs

@@ -83,8 +83,8 @@ config :ex_aws, :s3,
   scheme: "https://"
 
 config :pleroma, Pleroma.Uploaders.IPFS,
-  post_gateway_url: nil,
-  get_gateway_url: nil
+  post_gateway_url: "http://localhost:5001",
+  get_gateway_url: "http://localhost:8080"
 
 config :pleroma, :emoji,
   shortcode_globs: ["/emoji/custom/**/*.png"],