add test for utf8 issue (497)

[pjfanning]

• UTF8Reader throws"Need to move partially decoded character; buffer not modifiable" when read only one chinese char #497 is annotated as if the issue exists in our TOML parser (as well as the CSV parser)
• this test may not be a good one but it seems to indicate that the issue does not exist in the TOML parser

[pjfanning]

@yawkat could you review if you have time?

@cowtowncoder - GitHub CI is refusing to run the CI due to exceeding costs and bills - I thought the CI was free for open source (maybe within limits). - see https://github.com/FasterXML/jackson-dataformats-text/actions/runs/13443367760

[cowtowncoder]

@yawkat could you review if you have time?

@cowtowncoder - GitHub CI is refusing to run the CI due to exceeding costs and bills - I thought the CI was free for open source (maybe within limits). - see https://github.com/FasterXML/jackson-dataformats-text/actions/runs/13443367760

I actually even pay for FasterXML, fwtw. So not sure what racked up costs. Maybe newish cascading rebuilds...

[pjfanning]

I suspect the cascading rebuilds are a factor. It might be cheaper to run builds on the a daily or weekly schedule (ie once a day or once a week).

[cowtowncoder]

Yeah it'd be cheaper but from usability perspective quicker feedback loop is pretty valuable -- esp. when there are multiple merges per day. Daily might still work, weekly has too slow feedback loop for sure.

But will keep my eyes peeled for usage; this is first time I've noticed running out of quote so not yet a big problem I think.