Merge bitcoin#20368: ci: Remove redundant valgrind fuzz task

fa92cf2 ci: Remove redundant valgrind fuzz task (MarcoFalke)

Pull request description:

  This task has several issues:

  * It slows down other tasks and times out: It needs a lot of resources (CPU, RAM, time), because it builds more than 100 fuzzers, clones a 2 GB repo with 100k seeds and pipes them all through valgrind
  * It doesn't add a lot of value: Except for one issue in the boost time library, it hasn't found any issues that the existing fuzz,asan,ubsan fuzzer has already found
  * It is redundant: It is already run in the bitcoin-core/qa-assets repo on every push of new seeds and once daily

  Fix all issues by removing it here.

Top commit has no ACKs.

Tree-SHA512: 76d16a3e5afc79ba9d89cfeb915d7e66fd1ad4e2035ae4ccd30a21cc060bfba3fb6a904346b7c41606e69d972e86bf660df962673028689227cc26072bba24bd

.cirrus.yml

@@ -112,14 +112,6 @@ task:
   env:
     FILE_ENV: "./ci/test/00_setup_env_native_fuzz.sh"
 
-task:
-  name: 'x86_64 Linux  [GOAL: install]  [focal]  [no depends, only system libs, fuzzers under valgrind]'
-  << : *GLOBAL_TASK_TEMPLATE
-  container:
-    image: ubuntu:focal
-  env:
-    FILE_ENV: "./ci/test/00_setup_env_native_fuzz_with_valgrind.sh"
-
 task:
   name: 'x86_64 Linux [GOAL: install]  [focal]  [multiprocess]'
   << : *GLOBAL_TASK_TEMPLATE