ci: update test agent to 1.28.0 (#14132)

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [ ] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Author: brettlangdon

.gitlab/services.yml

@@ -12,7 +12,7 @@
       DD_REMOTE_CONFIGURATION_REFRESH_INTERVAL: 5s
       DD_DOGSTATSD_NON_LOCAL_TRAFFIC: true
   testagent:
-    name: registry.ddbuild.io/images/mirror/dd-apm-test-agent/ddapm-test-agent:v1.27.4
+    name: registry.ddbuild.io/images/mirror/dd-apm-test-agent/ddapm-test-agent:v1.28.0
     alias: testagent
     variables:
       LOG_LEVEL: ERROR

docker-compose.yml

@@ -121,7 +121,7 @@ services:
         volumes:
           - ddagent:/tmp/ddagent:rw
     testagent:
-        image: ghcr.io/datadog/dd-apm-test-agent/ddapm-test-agent:v1.27.4
+        image: ghcr.io/datadog/dd-apm-test-agent/ddapm-test-agent:v1.28.0
         ports:
             - "127.0.0.1:9126:8126"
         volumes:

lib-injection/docker-compose.yml

@@ -18,7 +18,7 @@ services:
 
   # testagent is used to collect data from the library to validate.
   testagent:
-    image: ghcr.io/datadog/dd-apm-test-agent/ddapm-test-agent:v1.27.4
+    image: ghcr.io/datadog/dd-apm-test-agent/ddapm-test-agent:v1.28.0
     ports:
       - "8126:8126"
 

tests/snapshots/tests.integration.test_trace_stats.test_measured_span_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "child_stats",
         "Resource": "child_stats",
         "Service": null,
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 10,
@@ -21,7 +21,7 @@
         "Name": "parent",
         "Resource": "parent",
         "Service": null,
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 20,

tests/snapshots/tests.integration.test_trace_stats.test_sampling_rate[0.0]_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "operation",
         "Resource": "operation",
         "Service": null,
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 10,

tests/snapshots/tests.integration.test_trace_stats.test_sampling_rate[1.0]_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "operation",
         "Resource": "operation",
         "Service": null,
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 10,

tests/snapshots/tests.integration.test_trace_stats.test_single_span_sampling[sampling_rule0]_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "parent",
         "Resource": "parent",
         "Service": "test",
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 1,

tests/snapshots/tests.integration.test_trace_stats.test_single_span_sampling[sampling_rule1]_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "parent",
         "Resource": "parent",
         "Service": "test",
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 1,

tests/snapshots/tests.integration.test_trace_stats.test_stats_30_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "name",
         "Resource": "/users/list",
         "Service": "abc",
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 30,

tests/snapshots/tests.integration.test_trace_stats.test_stats_errors_tracestats.json

@@ -7,7 +7,7 @@
         "Name": "name",
         "Resource": "/users/list",
         "Service": "abc",
-        "Type": null,
+        "Type": "",
         "HTTPStatusCode": 0,
         "Synthetics": false,
         "Hits": 30,