Taahir Ahmed 2d64d10d74 Deflake pod identity signer test using synctest (#1610) ...

I've seen this test flake at least once due to (I think) the way we are
truncating the timestamp for the NotBefore checks.

Replace all the clock injection stuff with synctest. No failures after
100 runs using `stress`.


```
taahm@taahm1 /u/l/g/h/t/p/s/substrate (deflake-signer)> go test ./cmd/podcertcontroller/...
?   	github.com/agent-substrate/substrate/cmd/podcertcontroller	[no test files]
ok  	github.com/agent-substrate/substrate/cmd/podcertcontroller/internal/podcertificate	0.013s
ok  	github.com/agent-substrate/substrate/cmd/podcertcontroller/internal/podidentitysigner	0.031s
?   	github.com/agent-substrate/substrate/cmd/podcertcontroller/internal/rendezvous	[no test files]
?   	github.com/agent-substrate/substrate/cmd/podcertcontroller/internal/servicednssigner	[no test files]
?   	github.com/agent-substrate/substrate/cmd/podcertcontroller/internal/signercontroller	[no test files]
```

```
taahm@taahm1 /u/l/g/h/t/p/s/substrate (deflake-signer) [1]> stress -count 100 go test ./cmd/podcertcontroller/...
5s: 24 runs so far, 0 failures, 8 active
10s: 48 runs so far, 0 failures, 8 active
15s: 63 runs so far, 0 failures, 8 active
20s: 78 runs so far, 0 failures, 8 active
25s: 89 runs so far, 0 failures, 8 active
27s: 100 runs total, 0 failures
```

2026-09-11 10:35:57 -07:00

..

internal

Deflake pod identity signer test using synctest (#1610)

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main.go

Deflake pod identity signer test using synctest (#1610)

2026-09-11 10:35:57 -07:00