fix: Segment number into word instead of chars (#271)

[dqkqd]

Pull Request

Related issue

Fixes #271

What does this PR do?

• Try to return Match if a string can be represented as number in AhoSegmentedStrIter
• Add numbers to existing testcases
• Add more 2 more testcases for segmenting and tokenizing number: segmenter_segment_number and tokenize_number

PR checklist

Please check if your PR fulfills the following requirements:

• Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
• Have you read the contributing guidelines?
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[ManyTheFish]

Hello @dqkqd, thank you for the work!
LGTM, we may want to go further by categorizing the tokens as TokenKind::Number in the Classifier

But it would be better in another PR

[ManyTheFish]

bors merge

[meili-bors]

Build succeeded:

• tests
• Run Rustfmt
• Run Clippy