Replace chemical spreadsheet with comp tox query script

[sgosline]

Currently we are using a static file that is pulled regularly from comptox to get chemical metadata. These are no here:
https://github.com/PNNL-CompBio/srpAnalytics/blob/main/data/CCDBatch_2022-01-26_AND_2021_11_05.xlsx

They are referenced in the sample mapping script here:

srpAnalytics/sampleChemMapping/mapSamplesToChems.R

Line 217 in a810f2a

chemMeta<-rio::import(comptoxfile)|>#,

And eventually merged with a manual mapping of chemical Ids to comptox ids here:

srpAnalytics/sampleChemMapping/mapSamplesToChems.R

Line 234 in a810f2a

chemMeta <- chemMeta%>%

There are two issues with this:

1. the comptox data can be queried automatically, via the API here. This can be fixed now, as there is a way to collect comp tox data directly from the website. Use the API to collect the data instead of doing a static query.
   https://www.epa.gov/comptox-tools/computational-toxicology-and-exposure-apis-about (we'll have to get an API key and add it to github secrets)
2. The mapping is provided by the tanguay lab and we need a way to account for additional chemicals. Not sure how to fix this just yet.

For now we can focus on #1.

[christinehc]

Fixed in bf9ac33.