Update ml-nlp-elser.asciidoc

[jun-sun-9527]

Remove extra quotes.

[cla-checker-service[bot]]

❌ Author of the following commits did not sign a Contributor Agreement: 1929629f17c58838397653b9e1d1e3fe580391d4

Please, read and sign the above mentioned agreement if you want to contribute to this project

[github-actions[bot]]

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[szabosteve]

Hi @jun-sun-9527, Thank you for your contribution! Do you mind signing the CLA? It is required for merging the PR. Thank you!