Fix a few typos in the vignette

[csoneson]

Hi @MarkusMuck - out of curiosity I was reading through the vignette and found a few typos 🙂

In addition:

• it looks like the score filtering doesn't do anything in the example data (all scores are above 10):

  peakCombiner/vignettes/peakCombiner.Rmd

  Line 596 in a9b00ef

  #### Filter for enrichment value

• should this refer to a specific section (not "Relevant Section")?

  peakCombiner/vignettes/peakCombiner.Rmd

  Line 52 in a9b00ef

  If you can’t provide data for the optional columns, prepare_input_regions adds sensible defaults for you (see “Relevant Section”).

• it may be good to check if you really need all the packages that are currently listed in Imports/Suggests - e.g., is tidyverse really needed (or are the individual components enough), are devtools, lintr, styler and usethis needed by the user (also utils does not seem to be used)?