Use host_256_fingerprint for diego-ssh

[kart2bc]

• Read the Contributing document.

Summary

Use host_256_fingerprint for diego-ssh
#1014

root@4649106b995b:/# ./repo/scripts/docker/test.bash diego-ssh/cmd/ssh-proxy
Sourcing: built-binaries/proxy/run.bash
Sourcing: built-binaries/nats-server/run.bash
Setting env: DB_USER
Setting env: DB_PASSWORD
Verifying: verify_go repo/src/code.cloudfoundry.org/diego-ssh/cmd/ssh-proxy
go version go1.25.5 linux/amd64
Verifying: verify_go_version_match_bosh_release repo
Verifying: verify_gofmt repo/src/code.cloudfoundry.org/diego-ssh/cmd/ssh-proxy
Verifying: verify_govet repo/src/code.cloudfoundry.org/diego-ssh/cmd/ssh-proxy
Verifying: verify_staticcheck repo/src/code.cloudfoundry.org/diego-ssh/cmd/ssh-proxy
booting mysqlconnection established to mysql
[1768411737] SSH Proxy Suite - 54/54 specs - 7 procs •••••••••••••••••••••••••••••••••••••••••••••••••••••• SUCCESS! 4m15.353795074s 
[1768411737] Config Suite - 15/15 specs - 7 procs ••••••••••••••• SUCCESS! 25.871890887s 

Ginkgo ran 2 suites in 4m45.84921484s
Test Suite Passed

root@4649106b995b:/# ./repo/scripts/docker/test.bash diego-ssh/routes       
Sourcing: built-binaries/proxy/run.bash
Sourcing: built-binaries/nats-server/run.bash
Setting env: DB_USER
Setting env: DB_PASSWORD
Verifying: verify_go repo/src/code.cloudfoundry.org/diego-ssh/routes
go version go1.25.5 linux/amd64
Verifying: verify_go_version_match_bosh_release repo
Verifying: verify_gofmt repo/src/code.cloudfoundry.org/diego-ssh/routes
Verifying: verify_govet repo/src/code.cloudfoundry.org/diego-ssh/routes
Verifying: verify_staticcheck repo/src/code.cloudfoundry.org/diego-ssh/routes
booting mysqlconnection established to mysql
Running Suite: Routes Suite - /repo/src/code.cloudfoundry.org/diego-ssh/routes
==============================================================================
Random Seed: 1768412502 - will randomize all specs

Will run 4 of 4 specs
Running in parallel across 7 processes
••••

Ran 4 of 4 Specs in 0.054 seconds
SUCCESS! -- 4 Passed | 0 Failed | 0 Pending | 0 Skipped


Ginkgo ran 1 suite in 2.323735936s

Backward Compatibility

Breaking Change? No

[winkingturtle-vmw]

@kart2bc Can you also please revert these two commits referenced here (#1014) ?