chore: Update package dependencies / package-locks

[kfranqueiro]

I happened to need to nuke my packages/*/node_modules before releasing today, and noticed that in the process, some package-lock files changed. This in turn led me to canvas for issues in our package-locks.

What I found / what this PR fixes:

• mdc-list doesn't need a package-lock
• mdc-snackbar had some outdated dependencies (probably due to it being worked on prior to our last release), which caused npm to want to create a package-lock when it doesn't need one
• mdc-dialog and mdc-drawer's package-locks only need to reference their third-party dependencies

Note that I'm running npm 6.5.0; it's possible that some of these changes (in particular the changes to mdc-dialog and mdc-drawer) have to do with npm updates, but it's also possible they were simply the result of cleaning out packages/*/node_modules.

[codecov-io]

Codecov Report

Merging #4191 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #4191   +/-   ##
======================================
  Coverage    98.5%   98.5%           
======================================
  Files         127     127           
  Lines        5629    5629           
  Branches      747     747           
======================================
  Hits         5545    5545           
  Misses         84      84

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[acdvorak]

LGTM!

[mdc-web-bot]

All 754 screenshot tests passed for commit f79bc80 vs. master! 💯🎉