build(deps): bump actions/setup-go from 6.1.0 to 6.4.0

Bumps [actions/setup-go](https://github.com/actions/setup-go) from 6.1.0 to 6.4.0.
- [Release notes](https://github.com/actions/setup-go/releases)
- [Commits](actions/setup-go@4dc6199...4a36011)

---
updated-dependencies:
- dependency-name: actions/setup-go
  dependency-version: 6.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

build(deps): bump actions/setup-go from 6.1.0 to 6.4.0

Bumps [actions/setup-go](https://github.com/actions/setup-go) from 6.1.0 to 6.4.0.
- [Release notes](https://github.com/actions/setup-go/releases)
- [Commits](actions/setup-go@4dc6199...4a36011)

---
updated-dependencies:
- dependency-name: actions/setup-go
  dependency-version: 6.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

action.yml: update gitops pusher to get precedence fix

Update gitops pusher dependency to get a fix for credential precedence.
Previously users attempting to authenticate with an API and the latest
version of the action would hit an error due to the gitops pusher
incorrectly trying to do a token exchange operation.

Updates #71

Signed-off-by: Mario Minardi <mario@tailscale.com>

action.yml: add support for workload identity federation

Add support for authenticating via workload identity federation.

Updates tailscale/corp#34172

Signed-off-by: Mario Minardi <mario@tailscale.com>

action.yml: update dependencies

Update actions/setup-go to its latest version and pin to this version.

Use go 1.25.5 in the aforementioned action (latest at the time of
writing and to match v1.92.1 of tailscale).

Update pinned gitops-pusher sha to v1.92.1 in tailscale.

Fixes #51
Fixes #66

Signed-off-by: Mario Minardi <mario@tailscale.com>

action.yml: bump gitops-pusher version (#47)

Pick up a fix from tailscale/tailscale#14296

Merge pull request #42 from tailscale/irbekrm/bump_deps

README.md,action.yml: bump versions

action: bump version of setup-go action

Most notably, this moves from node16 to node20.

Signed-off-by: Will Norris <will@tailscale.com>

action.yml: recombine gitops-pusher calls

We previously split the gitops-pusher steps based on which auth
variables were set due to a bug in the gitops-pusher tool itself.  That
as fixed in tailscale/tailscale#11025, so we can now recombine these.

Update to latest tagged version of tailscale to pull in the fix, and
bump the go version while we're at it.

Co-authored-by: Mario Minardi <mario@tailscale.com>
Signed-off-by: Will Norris <will@tailscale.com>

Merge pull request #34 from tailscale/mpminardi/oauth-fix

action.yml: add separate steps for API key and OAuth flows