TeamCity: Usability improvements : tag builds to distinguish nightly builds vs ad hoc builds, add project descriptions

[SarahFrench]

This PR is to address two areas where users of the new project might be confused:

• Understanding what the new projects are used for
• Understanding which builds are relevant to a release cut, when the timing of builds isn't strongly related to being a nightly test anymore.

To address these problems I'm going to add descriptions to projects in TeamCity, and also add a step to build configurations so they automatically tag themselves based on how they're triggered.

Builds triggered by the cron schedule at night will be labelled nightly-YYYY-MM-DD nightly-test, with the date in the tag. All other builds are tagged with one-off-build. Builds know if they're triggered by cron or not based on whether there's details about a user who triggered a given build (directly or indirectly, via dependencies)

Here's a test project where I set this up - if you trigger a build it'll be tagged appropriately. Note: this project has none of the ENVs set up, so all the builds will fail their tests but they'll be able to do the tagging fine.

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If this PR is for Terraform, I acknowledge that I have:

• Read Write release notes before writing my release note below.

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 7 files changed, 35 insertions(+), 7 deletions(-))
Terraform Beta: Diff ( 7 files changed, 35 insertions(+), 7 deletions(-))

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 7 files changed, 34 insertions(+), 7 deletions(-))
Terraform Beta: Diff ( 7 files changed, 34 insertions(+), 7 deletions(-))

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 7 files changed, 34 insertions(+), 7 deletions(-))
Terraform Beta: Diff ( 7 files changed, 34 insertions(+), 7 deletions(-))

[SarahFrench]

I've updated this PR to tag nightly tests with a static tag, instead of one that includes the date. This is because it'll be easier for users to use the 'filter by tags' feature to view only nightly test builds, and then look at the date information themselves. The old solution of each tag saying what night the build corresponds to helps users scan down the list of builds with their eyes but makes the filtering feature less usable.

See the filter by tags feature here, and how the old tags with dates in them could cause a problem over a long time: