Add a short (ttl-based) cache to AccountAPI.get_quotas()

[frivoire]

The goal is to optimize usecases like this :

api = AccountAPI(...)
api.has_quota(organization=organization, resource='servers', used=10)
api.has_quota(organization=organization, resource='volumes', used=10)
api.has_quota(organization=organization, resource='ips', used=10)

=> we check several quotas of the same organization in a very short period of time, typically within less than 1sec

In that usecase, the current AccountAPI does 3 calls to API-account, which is sub-optimal.
But we can easily cache "in-ram" the response to get_quotas(), because it's getting all quotas of a given organization, and re-use it for the 2nd and 3rd call.

NB: currently, each call to api-account to get quotas takes ~60 ms, so each call avoided is a lot :)

[codecov-io]

Codecov Report

Merging #24 into develop will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           develop    #24   +/-   ##
======================================
  Coverage      100%   100%           
======================================
  Files            4      4           
  Lines           99    101    +2     
  Branches        21     21           
======================================
+ Hits            99    101    +2

Impacted Files	Coverage Δ
scaleway/apis/api_account.py	100% <100%> (ø)	⬆️

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[jerome-quere]

LGTM

[lodow]

LGTM