fix: can't run multiple services on k8s (#3395)

Fix Issue: https://github.com/woodpecker-ci/woodpecker/issues/3288

The way the pod service starts up makes it impossible to run two or more
pipelines at the same time when we have a service section.

The idea is to set the name of the service in the same way we did for
the pod name.

Pipeline: 

```yaml

services:
  mydb:
    image: mysql
    environment:
      - MYSQL_DATABASE=test
      - MYSQL_ROOT_PASSWORD=example
    ports:
      - 3306/tcp
steps:
  get-version:
    image: ubuntu
    commands:
      - ( apt update && apt dist-upgrade -y && apt install -y mysql-client 2>&1 )> /dev/null
      - sleep 30s # need to wait for mysql-server init
      - echo 'SHOW VARIABLES LIKE "version"' | mysql -uroot -hmydb test -pexample
```

Running more than one pipeline result:


![image](https://github.com/woodpecker-ci/woodpecker/assets/22245125/e512309f-0d1e-4125-bab9-2357a710fedd)

---------

Co-authored-by: elias.souza <elias.souza@quintoandar.com.br>

pipeline/backend/kubernetes/pod_test.go

@@ -51,7 +51,7 @@ func TestStepToPodName(t *testing.T) {
 	assert.EqualValues(t, "wp-01he8bebctabr3kg", name)
 	name, err = stepToPodName(&types.Step{UUID: "01he8bebctabr3kg", Name: "postgres", Type: types.StepTypeService})
 	assert.NoError(t, err)
-	assert.EqualValues(t, "postgres", name)
+	assert.EqualValues(t, "wp-svc-01he8bebctabr3kg-postgres", name)
 }
 
 func TestStepLabel(t *testing.T) {