Resolves#11318.
* Adds `TestConfig.attachments` public API. (We opted to not implement an analog to the async `TestInfo.attach(…)` API.)
* Adds `TestConfig.attachments` to common reporters.
* Dogfoods some git and CI-info inference to generate useful atttachments
* Updates HTML Reporter to include a side bar to present a pre-defined set of attachments (a.k.a git/commit context sidebar)
Here's what it looks like:
<img width="1738" alt="Screen Shot 2022-03-21 at 3 23 28 PM" src="https://user-images.githubusercontent.com/11915034/159373291-8b937d30-fba3-472a-853a-766018f6b3e2.png">
See `tests/playwright-test/reporter-html.spec.ts` for an example of usage (for dogfood-ing only). In the future, if this becomes user-facing, there the Global Setup bit would likely become unnecessary (as would interaction with attachments array); there would likely just be a nice top-level config and/or CLI flag to enable collecting of info.
Previously, reporter would look for a stack frame directly in the test file.
Often times, that is not a top stack frame, especially when the test uses
some helper functions.
This changes error snippets and locations to use the top frame. When top
frame does not match the test file, we additionally show the location
to avoid confusion:
```
1) a.spec.ts:7:7 › foobar ========================================================================
Error: oh my
at helper.ts:5
3 |
4 | export function ohMy() {
> 5 | throw new Error('oh my');
| ^
6 | }
7 |
at ohMy (.../reporter-base-should-print-codeframe-from-a-helper/helper.ts:5:15)
at .../reporter-base-should-print-codeframe-from-a-helper/a.spec.ts:8:9
at FixtureRunner.resolveParametersAndRunHookOrTest (.../src/fixtures.ts:281:12)
```
