initdata: use digest hash directly

Use initdata.digest directly rather than HEX in attestation policy

Signed-off-by: Qi Feng Huo <huoqif@cn.ibm.com>

src/cloud-api-adaptor/docs/initdata.md

@@ -170,12 +170,10 @@ For example, for [IBM SE](https://github.com/confidential-containers/trustee/blo
 ```
 allow if {
     ...
-    input["se.user_data"] == "353261663331373864643761643462663535316536323962383462343562666431666265313433346239383031323032363731383161653335373565613230636139303133623865616466333164323765656437666632353532643530306566"
+    input["se.user_data"] == "52af3178dd7ad4bf551e629b84b45bfd1fbe1434b980120267181ae3575ea20ca9013b8eadf31d27eed7ff2552d500ef"
     ...
 }
 ```
 
-`se.user_data` is the HEX of the initdata digest string `52af3178dd7ad4bf551e629b84b45bfd1fbe1434b980120267181ae3575ea20ca9013b8eadf31d27eed7ff2552d500ef`.
-
 ## TODO
 A large policy bodies that cannot be provisioned via IMDS user-data, the limitation depends on providers IMDS limitation. We need add checking and limitations according to test result future.