Merge bitcoin/bitcoin#30869: ci: Print inner env, Make ccache config more flexible

fa99e4521b ci: Allow CCACHE_DIR bind mount (MarcoFalke)
fa252da0b9 ci: Remove hardcoded CCACHE_DIR in cirrus (MarcoFalke)
fa146904e1 ci: Bump default CCACHE_MAXSIZE to 500M (MarcoFalke)
aaaa7cf8ba cirrus: Drop CCACHE_NOHASHDIR (MarcoFalke)
fa7ca182a9 ci: Print inner env (MarcoFalke)

Pull request description:

  The outer env is printed when the `/tmp/env-$USER-$CONTAINER_NAME` is created. There is also a separate env printed when building the container image (usually with default values).

  To confirm that the inner container env is correctly derived from the outer env, and not from the default build env, print it a third time.

ACKs for top commit:
  l0rinc:
    utACK fa99e4521b
  willcl-ark:
    ACK fa99e4521b

Tree-SHA512: 59fd3262d551e09224866e31c14ca865461e81abbe00b83391fe3a9c7ada30fd2fd0272e4aa812df2712433ac7594d1a55cf674248b341359cec09c8d3f0c58b

ci/test/00_setup_env.sh

@@ -53,12 +53,12 @@ export RUN_FUZZ_TESTS=${RUN_FUZZ_TESTS:-false}
 export BOOST_TEST_RANDOM=${BOOST_TEST_RANDOM:-1}
 # See man 7 debconf
 export DEBIAN_FRONTEND=noninteractive
-export CCACHE_MAXSIZE=${CCACHE_MAXSIZE:-100M}
+export CCACHE_MAXSIZE=${CCACHE_MAXSIZE:-500M}
 export CCACHE_TEMPDIR=${CCACHE_TEMPDIR:-/tmp/.ccache-temp}
 export CCACHE_COMPRESS=${CCACHE_COMPRESS:-1}
 # The cache dir.
 # This folder exists only on the ci guest, and on the ci host as a volume.
-export CCACHE_DIR=${CCACHE_DIR:-$BASE_SCRATCH_DIR/.ccache}
+export CCACHE_DIR="${CCACHE_DIR:-$BASE_SCRATCH_DIR/ccache}"
 # Folder where the build result is put (bin and lib).
 export BASE_OUTDIR=${BASE_OUTDIR:-$BASE_SCRATCH_DIR/out}
 # The folder for previous release binaries.