Fix MetricFormatterTests

[aokj4ck]

Description

• MastodonMetricFormatter accepts a number such as 1234, and converts it to an abbreviated form: "1.2K" in the US and "1,2K" in the EU.
  • Add MastodonMetricFormatter.abbreviatedGroupingSeparator to allow changing the separator.
  • The default values of abbreviatedGroupingSeparator are: period in the US and comma in the EU.
  • Update the unit tests to explicitly assign abbreviatedGroupingSeparator = "," for EU-styled test assertions.
  • Update the test_thousandNinetynineFormat() test function to explicitly test abbreviatedGroupingSeparator with both EU (,) and US (.) separators.
• Fix MastodonTests.testWebFinger() to fulfill the test expectation exactly once, and on the main thread.
• Update MastodonTests.testConnectOnion() to report an XCTFail() instead of an assertion failure so that the process can exit cleanly and report the test failure instead of halting.
  • testConnectOnion is currently failing, there may be additional servers that this works with but I haven't been able to run a passing test.

[whattherestimefor]

typo - decimel vs. decimal