packer/scylla.json: Add `apt-get update` after kernel package removal

[yaronkaikov]

From time to time we get the following error during Azure build:

�[0;32m    azure: Reading state information...�[0m
 �[1;31m==> azure: E: Unable to locate package linux-azure-lts-22.04�[0m
 �[1;31m==> azure: E: Couldn't find any package by glob 'linux-azure-lts-22.04'�[0m
 �[1;31m==> azure: E: Couldn't find any package by regex 'linux-azure-lts-22.04'�[0m
 �[1;32m==> azure: Provisioning step had errors: Running the cleanup provisioner, if present...�[0m
 �[1;32m==> azure:
 ==> azure: Deleting individual resources ...�[0m

Couldn't find a main reason for this, as it can't be repreduced all time.

As suggested by @mykaul, adding apt-get update after kernel package pruge command

Fixes: https://github.com/scylladb/scylla-pkg/issues/3601

[yaronkaikov]

Verification: Running https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/ on a small fleet using the master branch (without my change). 3 out of 4 failed with the relevant error message:

https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/260/ https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/261/ - FAILED https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/262/ - FAILED https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/263/ - FAILED

Running from my branch (with the apt-get update)

All jobs passed: https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/264/ https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/265/ https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/266/ https://jenkins.scylladb.com/job/scylla-master/job/releng-testing/job/azure-image/267/