rebase: Bump github.com/hashicorp/vault from 1.4.2 to 1.9.9

Bumps [github.com/hashicorp/vault](https://github.com/hashicorp/vault) from 1.4.2 to 1.9.9.
- [Release notes](https://github.com/hashicorp/vault/releases)
- [Changelog](https://github.com/hashicorp/vault/blob/main/CHANGELOG.md)
- [Commits](https://github.com/hashicorp/vault/compare/v1.4.2...v1.9.9)

---
updated-dependencies:
- dependency-name: github.com/hashicorp/vault
  dependency-type: indirect
...

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

vendor/github.com/cenkalti/backoff/v3/timer.go

@@ -0,0 +1,35 @@
+package backoff
+
+import "time"
+
+type Timer interface {
+	Start(duration time.Duration)
+	Stop()
+	C() <-chan time.Time
+}
+
+// defaultTimer implements Timer interface using time.Timer
+type defaultTimer struct {
+	timer *time.Timer
+}
+
+// C returns the timers channel which receives the current time when the timer fires.
+func (t *defaultTimer) C() <-chan time.Time {
+	return t.timer.C
+}
+
+// Start starts the timer to fire after the given duration
+func (t *defaultTimer) Start(duration time.Duration) {
+	if t.timer == nil {
+		t.timer = time.NewTimer(duration)
+	} else {
+		t.timer.Reset(duration)
+	}
+}
+
+// Stop is called when the timer is not used anymore and resources may be freed.
+func (t *defaultTimer) Stop() {
+	if t.timer != nil {
+		t.timer.Stop()
+	}
+}