silverwind 74f0c84fa4
Enable more `revive` linter rules ()
Noteable additions:

- `redefines-builtin-id` forbid variable names that shadow go builtins
- `empty-lines` remove unnecessary empty lines that `gofumpt` does not
remove for some reason
- `superfluous-else` eliminate more superfluous `else` branches

Rules are also sorted alphabetically and I cleaned up various parts of
`.golangci.yml`.
..
db.go Enable more `revive` linter rules ()
db_test.go Fix bug hidden on CI and make ci failed if tests failure ()
hash.go Use `crypto/sha256` ()
main_test.go Implement FSFE REUSE for golang files ()
tests.go Rename `Sync2` -> `Sync` ()