CASMTRIAGE-7294 upgrade cert-manager in prerequisites.sh if cray-drydock is not on the correct version

[leliasen-hpe]

Description

In CSM 1.6, the latest cray-drydock version is 2.18.4. In that version, cray-drydock creates the cert-manager namespace. If the system has already been upgraded to an early version on CSM 1.6, then cert-manager has likely been upgraded and cray-drydock has not. The cray-drydock chart fails to upgrade when cert-manager is installed. This PR adds logic in the case of a CSM 1.6 to CSM 1.6 upgrade. It allows cray-drydock to be upgraded by uninstalling cert-manager, then upgrading drydock, then reinstalling cert-manager. Again, this is only used on a CSM 1.6 to CSM 1.6 upgrade.

Checklist

• If I added any command snippets, the steps they belong to follow the prompt conventions (see example).
• If I added a new directory, I also updated .github/CODEOWNERS with the corresponding team in Cray-HPE.
• My commits or Pull-Request Title contain my JIRA information, or I do not have a JIRA.

[dborman-hpe]

LGTM

[leliasen-hpe]

I tested the latest version of this block on gamora and observed that it worked properly. Here is a section of the output when run with 'set -x'

+ '[' 0 -eq 0 ']'
++ helm get metadata -n loftsman cray-drydock -o json
++ jq -r .version
+ drydock_vers=2.18.2
+ major=2
+ minor=18
+ patch=4
+ drydock_major=2
+ drydock_minor_patch=18.2
+ drydock_patch=2
+ drydock_minor=18
+ '[' 2 -lt 2 ']'
+ '[' 2 -eq 2 ']'
+ '[' 18 -lt 18 ']'
+ '[' 2 -eq 2 ']'
+ '[' 18 -eq 18 ']'
+ '[' 2 -lt 4 ']'
+ needs_upgrade=1
+ '[' 1 -ne 0 ']'
+ echo 'cray-drydock version [2.18.2] less than 2.18.4 and needs to be upgraded.'
cray-drydock version [2.18.2] less than 2.18.4 and needs to be upgraded.
+ echo 'Cray-drydock will be upgraded and the cert-manager namespace will be redeployed.'
Cray-drydock will be upgraded and the cert-manager namespace will be redeployed.

[leliasen-hpe]

In early CSM 1.6 versions, helm is an earlier version and does not have the metadata -o json option. In the case where this is run on an early CSM 1.6 system, this is the output. It still functions correctly.

++ helm get metadata -n loftsman cray-drydock -o json
++ jq -r .version
Error: unknown shorthand flag: 'o' in -o
+ drydock_vers=
+ major=2
+ minor=18
+ patch=4
+ drydock_major=
+ drydock_minor_patch=
+ drydock_patch=
+ drydock_minor=
+ '[' -lt 2 ']'
./upgrade_drydock.sh: line 48: [: -lt: unary operator expected
+ '[' -eq 2 ']'
./upgrade_drydock.sh: line 50: [: -eq: unary operator expected
+ '[' -eq 2 ']'
./upgrade_drydock.sh: line 52: [: -eq: unary operator expected
+ [[ '' == '' ]]
+ needs_upgrade=1
+ '[' 1 -ne 0 ']'
+ echo 'cray-drydock version [] less than 2.18.4 and needs to be upgraded.'
cray-drydock version [] less than 2.18.4 and needs to be upgraded.
+ echo 'Cray-drydock will be upgraded and the cert-manager namespace will be redeployed.'
Cray-drydock will be upgraded and the cert-manager namespace will be redeployed.