Merge bitcoin/bitcoin#30981: ci: add timestamps to cirrus jobs

f951f1f ci: add timestamps to cirrus jobs (willcl-ark)

Pull request description:

  Currently, debugging where time is spent in the cirrus jobs feels annoying, e.g. trying to see where time may be spent in bitcoin/bitcoin#30969

  Enable timestamps in the logs for more information.

ACKs for top commit:
  maflcko:
    review ACK f951f1f
  tdb3:
    Code Review ACK f951f1f
  hebasto:
    ACK f951f1f.

Tree-SHA512: 4ca6c3722013323e794339c39af3041a519e3ecf75216093c4ca99668c0932fe41cc547819f742a3e8a47709ec6baec976c542eb3848c0248f439841110a4e85

Author: fanquake

.cirrus.yml

@@ -1,5 +1,6 @@
 env:  # Global defaults
   CIRRUS_CLONE_DEPTH: 1
+  CIRRUS_LOG_TIMESTAMP: true
   PACKAGE_MANAGER_INSTALL: "apt-get update && apt-get install -y"
   MAKEJOBS: "-j10"
   TEST_RUNNER_PORT_MIN: "14000"  # Must be larger than 12321, which is used for the http cache. See https://cirrus-ci.org/guide/writing-tasks/#http-cache