configs/ot2_defconfig: select ca-certificates, curl, git, grep, sl, wget

[sfoster1]

overview

This PR adds some packages to the OT-2 defconfig to enable more complex workflows:

• ca-certificates to make sure the robot has root certs to hit HTTPS stuff
• git for pulling stuff from... git
• curl and wget for making requests and pulling data from HTTP
• grep for data and log inspection
• sl to make @sfoster1 happy

review requests

• can successfully clone a git repository via HTTPS
• can curl an HTTPS endpoint
• can wget an HTTPS resource
• can grep something
• chugga chugga choo choo

[theosanderson]

For info, I branched off this and I am not finding that this works:

# git remote add origin https://github.com/theosanderson/covid_serology_ot.git
# git push -u origin master
fatal: Unable to find remote helper for 'https'
# wget "https://bbcnews.com"
wget: not an http or ftp url: https://bbcnews.com
# 

Edit: possible this was a copy and paste problem with hidden characters, which I've since encountered. Sorry if this was a bad report!

[sfoster1]

Since it's technically still my own PR I can't approve, but I can confirm that git, curl, and wget from https endpoints works, as does the steam locomotive

[mcous]

Approving on behalf of @sfoster1 per his comment above