Add TimeConfig option to allow truncating of fractional seconds

[adriangb]

@samuelcolvin a couple of questions:

• Any input on how to fix the failing tests? It might take me a bit of work to actually grok what is going on during parsing, it's a lot of bytes, offsets, length += i, etc.
• Do you think we also need new parse_str methods? I was thinking not
• Should we call the parameter time_config: TimeConfig or add an empty date_config: DateConfig or are we certain we'll never want a config for dates?

[codecov[bot]]

Codecov Report

Merging #42 (275bed9) into main (0976d4f) will decrease coverage by 0.71%. The diff coverage is 84.61%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #42 +/- ## ========================================== - Coverage 99.87% 99.17% -0.71% ========================================== Files 6 6 Lines 822 847 +25 ========================================== + Hits 821 840 +19 - Misses 1 7 +6 ``` | [Impacted Files](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic) | Coverage Δ | | |---|---|---| | [src/lib.rs](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic#diff-c3JjL2xpYi5ycw==) | `100.00% <ø> (ø)` | | | [src/time.rs](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic#diff-c3JjL3RpbWUucnM=) | `97.43% <75.00%> (-2.57%)` | :arrow_down: | | [src/datetime.rs](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic#diff-c3JjL2RhdGV0aW1lLnJz) | `100.00% <100.00%> (ø)` | | | [src/duration.rs](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic#diff-c3JjL2R1cmF0aW9uLnJz) | `100.00% <100.00%> (ø)` | | ------ [Continue to review full report in Codecov by Sentry](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=continue&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic). > **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic) > `Δ = absolute (impact)`, `ø = not affected`, `? = missing data` > Powered by [Codecov](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=footer&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic). Last update [0976d4f...275bed9](https://app.codecov.io/gh/pydantic/speedate/pull/42?src=pr&el=lastupdated&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pydantic).

[adriangb]

please review