Rollup merge of #145255 - lune-climate:dec2flt-doc, r=ibraheemdev

dec2flt: Provide more valid inputs examples

I was just looking at the specifics of how the parsing is handled here and I wasn't sure if the examples were incomplete or the grammar below was misleading.

The grammar was correct so I figured I'd add these examples to clarify.

Author: jieyouxu