[9.0] add ci shared qualified-version script (backport #17311)

[mergify]

Release notes

[rn: skip]

What does this PR do?

Adds a shareable script for buildkite to get a fully-qualified version, including:

• the base version from ${LOGSTASH_HOME}/versions.yml
• the qualifier from optional VERSION_QUALIFIER environment variable
• the SNAPSHOT tag from either WORKFLOW_TYPE or RELEASE environment variables

Why is it important/What is the impact to the user?

In #17298 we are adding tasks to smoke-test built artifacts, so we need the qualified version. Instead of duplicating the logic yet again, I extracted it to a share-able helper. I plan to backport this and reuse it elsewhere.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] I have made corresponding change to the default configuration files (and/or docker env variables)
• [ ] I have added tests that prove my fix is effective or that my feature works

Author's Checklist

• [ ]

How to test this PR locally

Related issues

Use cases

Screenshots

Logs

Sourcing sets the QUALIFIED_VERSION environment variable

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (source .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
QUALIFIED_VERSION=9.1.0-SNAPSHOT
[success]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (RELEASE=1 source .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
QUALIFIED_VERSION=9.1.0
[success]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (WORKFLOW_TYPE=staging source .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION)) 
QUALIFIED_VERSION=9.1.0
[success]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (VERSION_QUALIFIER=beta1 WORKFLOW_TYPE=staging source .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
QUALIFIED_VERSION=9.1.0-beta1
[success]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (VERSION_QUALIFIER=beta1 source .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION)) 
QUALIFIED_VERSION=9.1.0-beta1-SNAPSHOT
[success]

Invoking outputs the qualified version, but doesn't set the env var (the % is my shell's way of saying that there was no trailing newline, and the commands "error" because the grep fails to find QUALIFIED_VERSION in the output of env ):

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (.buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))                 
9.1.0-SNAPSHOT%
[error: 1]    

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (RELEASE=1 .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
9.1.0%[error: 1]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (WORKFLOW_TYPE=staging .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
9.1.0%
[error: 1]

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (VERSION_QUALIFIER=beta1 WORKFLOW_TYPE=staging .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION))
9.1.0-beta1%
[error: 1] 

╭─{ rye@perhaps:~/src/elastic/logstash@main (build-script-qualified-version ✔) }
╰─● (VERSION_QUALIFIER=beta1 .buildkite/scripts/common/qualified-version.sh; (env | grep QUALIFIED_VERSION)) 
9.1.0-beta1-SNAPSHOT%
[error: 1]
~~~<hr>This is an automatic backport of pull request #17311 done by [Mergify](https://mergify.com).

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 5059003

cc @yaauie

[yaauie]

✅ Clean and Green 🎉