scripted-diff: validation: rename mandatory errors into block errors

Using "block" or "mempool" as the prefix in place of "mandatory" or "non-mandatory" is clearer
to a user. "non-mandatory" was renamed into "mempool" as part of #33050. This takes care of the
other half of this renaming as a scripted diff.

-BEGIN VERIFY SCRIPT-
sed -i 's/mandatory-script-verify/block-script-verify/g' $(git grep -l mandatory-script-verify)
-END VERIFY SCRIPT-

test/functional/interface_usdt_mempool.py

@@ -30,7 +30,7 @@ MEMPOOL_TRACEPOINTS_PROGRAM = """
 # include <uapi/linux/ptrace.h>
 
 // The longest rejection reason is 118 chars and is generated in case of SCRIPT_ERR_EVAL_FALSE by
-// strprintf("mandatory-script-verify-flag-failed (%s)", ScriptErrorString(check.GetScriptError()))
+// strprintf("block-script-verify-flag-failed (%s)", ScriptErrorString(check.GetScriptError()))
 #define MAX_REJECT_REASON_LENGTH        118
 // The longest string returned by RemovalReasonToString() is 'sizelimit'
 #define MAX_REMOVAL_REASON_LENGTH       9