chore: pluralize table names

[coadler]

Also populates the down migrations.

[codecov]

Codecov Report

Merging #463 (94013f7) into main (edd8345) will increase coverage by 4.27%.
The diff coverage is 42.30%.

@@            Coverage Diff             @@
##             main     #463      +/-   ##
==========================================
+ Coverage   63.72%   67.99%   +4.27%     
==========================================
  Files          74      160      +86     
  Lines         827     9278    +8451     
  Branches       79       79              
==========================================
+ Hits          527     6309    +5782     
- Misses        287     2345    +2058     
- Partials       13      624     +611     

Flag	Coverage Δ
unittest-go-macos-latest	62.64% <7.69%> (?)
unittest-go-ubuntu-latest	67.34% <42.30%> (?)
unittest-go-windows-2022	62.03% <7.69%> (?)
unittest-js	63.72% <ø> (ø)

Impacted Files	Coverage Δ
coderd/coderd.go	96.18% <ø> (ø)
database/migrate.go	45.00% <34.78%> (ø)
coderd/coderdtest/coderdtest.go	98.87% <100.00%> (ø)
httpmw/httpmw.go	100.00% <100.00%> (ø)
codersdk/workspacebuilds.go	65.38% <0.00%> (ø)
cli/clitest/clitest.go	93.33% <0.00%> (ø)
httpmw/workspaceagent.go	47.36% <0.00%> (ø)
coderd/parameters.go	65.38% <0.00%> (ø)
codersdk/files.go	66.66% <0.00%> (ø)
... and 80 more

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[kylecarbs]

Nice addition of the down migrations! 👇