According to https://golang.org/s/generatedcode the generated
Go code should have a comment matches the following regexp:
```
^// Code generated .* DO NOT EDIT\.$
```

Create dependabot.yml

This solves uber-go#139 by referencing actions by sha rather than directly by version.

We also update all of the actions we use at the same time.

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 3.1.1 to 3.1.4.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@d9f34f8...eaaf4be)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

This references fossa workflow actions by SHA, which uber-go#141 missed.

Bumps [actions/checkout](https://github.com/actions/checkout) from 4.0.0 to 4.1.1.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@1e31de5...b4ffde6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bumps [honnef.co/go/tools](https://github.com/dominikh/go-tools) from 0.3.3 to 0.4.6.
- [Release notes](https://github.com/dominikh/go-tools/releases)
- [Commits](dominikh/go-tools@v0.3.3...v0.4.6)

---
updated-dependencies:
- dependency-name: honnef.co/go/tools
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bumps [actions/cache](https://github.com/actions/cache) from 3.3.2 to 3.3.3.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@704facf...e12d46a)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bumps [actions/cache](https://github.com/actions/cache) from 3.3.3 to 4.0.0.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@e12d46a...13aacd8)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 3.1.4 to 3.1.5.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@eaaf4be...4fe8c5f)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

According to https://golang.org/s/generatedcode the generated
Go code should have a comment matches the following regexp:
```
^// Code generated .* DO NOT EDIT\.$
```