Fixed-case for multi-sentence titles

[mbollmann]

In paper titles with multiple sentences, the first word of non-initial sentences should probably be <fixed-case>d.

This happens e.g. here: How Good is Your Tokenizer? On the Monolingual Performance of Multilingual Language Models

Using our official Anthology BibTeX with the ARR templates, "on" will appear in the bibliography as all-lowercase.

[davidweichiang]

I wish we could fix this in the bst file instead…