fix missing blob size limit on validate call

[A-Stapleton]

Fixes an issue where the blob file size limit is not passed into the validate call resulting in file sizes growing beyond the limit.

When the code detects the current blob has exceeded the limits it rolls the sequence but calls ValidateAppendBlobClientAsync(...) without passing blobSizeLimitBytes, so the subsequent selection ignores the size limit (because the parameter defaults to null). That lets the sink pick an already‑too‑large blob and continue writing.

[A-Stapleton]

I can confirm all tests do pass, ran locally, think that failures a pipeline issue.