Use Knuth–Morris–Pratt algorithm for delimiter search in TextIO

[baeminbo]

I believe this PR can fix #32251 (it's closed but still not fully fixed. see this case) and #32249.

Fix #32249, #32251.

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[baeminbo]

R: @scwhittle, @Abacn

Hi @scwhittle, I see you're working on the PR #32258 for fixing the issue #32241. I created this PR to fix the issue #32251 , but I believe it can also fix #32249.

Hi @Abacn, I see you approved the PR #32298, but it cannot fix all the cases of #32241. Could you check it again?

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[scwhittle]

Thanks for putting this together, I got bogged down in trying to make startReading correct as well but it is probably best to fix separately.

startReading is incorrect in cases where the offset is smaller than the delimiter length, or smaller than where the headers end, where there is a BOM and headers etc which I uncovered when adding integration test of longer delimiters to sdks/java/core/src/test/java/org/apache/beam/sdk/io/TextIOReadTest.java

[baeminbo]

@scwhittle Could you continue to review? I added a commit to change the delimiter search algorithm. Thanks.

[scwhittle]

Just some minor cleanup comments. Thanks!

[scwhittle]

Run Java_IOs_Direct PreCommit

[scwhittle]

Waiting on tests to complete to merge

[baeminbo]

@scwhittle I fixed a bug at a commit which made the test failed. Could you continue to review this? Thanks.