feat(asm): meta struct enable by default for 3.0 (#12117)

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Author: christophe-papazian

ddtrace/settings/asm.py

@@ -73,7 +73,7 @@ class ASMConfig(Env):
     _iast_propagation_debug = Env.var(bool, IAST.ENV_PROPAGATION_DEBUG, default=False, private=True)
     _iast_telemetry_report_lvl = Env.var(str, IAST.ENV_TELEMETRY_REPORT_LVL, default=TELEMETRY_INFORMATION_NAME)
     _appsec_standalone_enabled = Env.var(bool, APPSEC.STANDALONE_ENV, default=False)
-    _use_metastruct_for_triggers = False
+    _use_metastruct_for_triggers = True
 
     _automatic_login_events_mode = Env.var(str, APPSEC.AUTOMATIC_USER_EVENTS_TRACKING, default="", parser=str.lower)
     # Deprecation phase, to be removed in ddtrace 3.0.0

releasenotes/notes/msgpack_for_appsec-e09c17e9cb568379.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - |
+    ASM: This introduces use of meta struct for appsec event reports. This will improve performances.
+    ASM will now require at least agent version 7.35.0 to work as expected.