Update warning message for rule S305 to address insecure block cipher…

… mode use (#10602)

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## Summary

This PR updates the warning message for rule S305 to accurately reflect
the security concern over using ECB mode in block ciphers, which is
considered insecure compared to other modes like CBC or CTR. The
previous message incorrectly mentioned AES as a [block cipher
mode](https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation),
which has been corrected to avoid confusion.

Ref: 

https://github.com/PyCQA/bandit/blob/c85576d903c213859634f4fbcb6304042442e62a/bandit/blacklists/calls.py#L99-L102


https://github.com/astral-sh/ruff/blob/825fd7c990e12569886127f7f7ca953b5516d327/crates/ruff_linter/src/rules/flake8_bandit/rules/suspicious_function_call.rs#L187-L216

## Test Plan

No testing required as the change is limited to a minor change of
warning message update.

crates/ruff_linter/src/rules/flake8_bandit/rules/suspicious_function_call.rs

@@ -220,7 +220,7 @@ pub struct SuspiciousInsecureCipherModeUsage;
 impl Violation for SuspiciousInsecureCipherModeUsage {
     #[derive_message_formats]
     fn message(&self) -> String {
-        format!("Use of insecure cipher mode, replace with a known secure cipher such as AES")
+        format!("Use of insecure block cipher mode, replace with a known secure mode such as CBC or CTR")
     }
 }