Enterprise integration tests are failing due to supposedly expired license

### Problem statement

Kong license has changed recently (it contains a version typed as int and not as string).

https://github.com/Kong/kubernetes-testing-framework/pull/1517 aims to bump the license action and fix that license parsing issue.

For some reason, the license is not being properly read.

Local tests show that 403s seen in test log are attributed to missing or expired license errors:

```
kong@ingress-controller-kong-5ff7f4b4cf-gs448:/$ env | grep LICEN
KONG_LICENSE_DATA={"license":{"payload":{"admin_seats":"5","customer":"automation","dataplanes":"","license_creation_date":"2026-04-13","license_expiration_date":"2026-05-20","license_key":"x","product_subscription":"Konnect Enterprise","support_plan":"None"},"signature":"x","version":1}}
kong@ingress-controller-kong-5ff7f4b4cf-gs448:/$
exit
root@4e14994a-76bd-480c-9334-6e6cf1d1d5af-control-plane:/# curl -v -XPOST 172.18.128.2:8001/consumer_groups -H "Kong-Admin-Token:X" ; echo
* Trying 172.18.128.2:8001...
* Connected to 172.18.128.2 (172.18.128.2) port 8001 (#0)
> POST /consumer_groups HTTP/1.1
> Host: 172.18.128.2:8001
> User-Agent: curl/7.88.1
> Accept: */*
> Kong-Admin-Token:X
>
< HTTP/1.1 403 Forbidden
< Date: Tue, 14 Apr 2026 09:24:10 GMT
< Content-Type: application/json; charset=utf-8
< Connection: keep-alive
< Access-Control-Allow-Origin: *
< X-Kong-Admin-Request-ID: z5PuaMdms4jp1F0jH2oTDZsRdE9NESNe
< Content-Length: 51
< X-Kong-Admin-Latency: 5
< Server: kong/3.4.3.25-enterprise-edition
<
* Connection #0 to host 172.18.128.2 left intact
{"message":"Enterprise license missing or expired"}
```

### Acceptance criteria

- [ ] Enterprise integration tests are passing on CI

Start by reading the referenced PR #1517 and the enterprise integration-test CI logs, then inspect how the Kong license is supplied to the test environment. Reproduce the 403 license error if possible and compare the license format used by the tests with the expected format. Done means the enterprise integration tests pass on CI.

Written by the indexing model from the issue text.