[erlang-client] Fix url path generation being passed to hackney_url

[dweinstein]

This change is attempting to fix a regression in URL Paths in the erlang-client. The current pet_store sample erlang-client does not work against the real petstore.swagger.io because of a regression in the Path introduced in cdc0076.

Currently if one makes a request for pet id 10 the api client will make a request for %0a instead.

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[dweinstein]

Looks like the change to the path generation was made in cdc0076 which was trying to fix another issue perhaps.

cdc0076#diff-8a7b672a5f73867d594118b21ae6930335ddfb72e820a10c1c94a2773a494e76R6-R24

Here's an example where the current sample client fails--we are supposed to be requesting pet id 10 but instead we request %0A:

2> petstore_pet_api:get_pet_by_id(#{}, 10, #{cfg => #{host => "https://petstore.swagger.io"}}).
[hackney trace 80 <0.275.0> 2023:02:26 18:39:25 4415] request 
   Content: [{module,hackney},
             {line,313},
             {method,get},
             {url,{hackney_url,hackney_ssl,https,<<"petstore.swagger.io">>,
                               <<"/v2/pet/\n">>,<<"/v2/pet/%0A">>,<<>>,<<>>, % <---- notice how 10 is converted to %0A
                               "petstore.swagger.io",443,<<>>,<<>>}},
             {headers,[]},
             {body,[]},
             {options,[]}]
[hackney trace 60 <0.275.0> 2023:02:26 18:39:25 4417] request without proxy 
   Content: [{module,hackney},{line,685}]
[hackney trace 60 <0.275.0> 2023:02:26 18:39:25 4425] connect 
   Content: [{module,hackney_connect},
             {line,32},
             {transport,hackney_ssl},
             {host,"petstore.swagger.io"},
             {port,443},
             {dynamic,true}]
[hackney trace 80 <0.275.0> 2023:02:26 18:39:25 4453] no socket in the pool 
   Content: [{module,hackney_pool},{line,88},{pool,default}]
[hackney trace 80 <0.275.0> 2023:02:26 18:39:25 4816] new connection 
   Content: [{module,hackney_pool},{line,94}]
[hackney trace 60 <0.275.0> 2023:02:26 18:39:25 4816] reuse a connection 
   Content: [{module,hackney_connect},{line,216},{pool,default}]
[hackney trace 40 <0.275.0> 2023:02:26 18:39:25 4817] perform request 
   Content: [{module,hackney_request},
             {line,106},
             {header_data,[<<"GET /v2/pet/%0A HTTP/1.1\r\n">>,
                           [[<<"Host">>,": ",<<"petstore.swagger.io">>,"\r\n"],
                            [<<"User-Agent">>,": ",<<"hackney/1.18.1">>,
                             "\r\n"],
                            "\r\n"]]},
             {perform_all,true},
             {expect,false}]
[hackney trace 80 <0.275.0> 2023:02:26 18:39:25 4930] got response 

cc @lixen-wg2 please let me know if you agree?

[wing328]

@dweinstein thanks for the PR. can you please PM me via Slack when you've time?

https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g

[wing328]

as discussed, let's move ahead with this change. i'll merge and update the samples.

[wing328]

samples updated via 6d71db3

[dweinstein]

thanks @wing328 sorry that I hadn't had the chance to make the tweaks to the mustache stuff for the integer handling. It's still on my list.

[wing328]

take your time.

in other generators, we use something like String.valueOf() to force the input (integer, double, string, etc) into string.

not sure if erlang has something similar.