fix(winston-transport, instrumentation-winston): get the correct severityText and severityNumber with winston.format.colorize() is used

[trentm]

Before this change the "log sending" feature of instr-winston would
incorrectly include ANSI color codes in the severityText for emitted
OTel LogRecords when the winston logger being instrumented was
configured with the colorize() formatter, e.g.:

const logger = winston.createLogger({
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.colorize(),
    winston.format.simple()
  ),
  ...

This is because the winston-transport.OpenTelemetryTransportV3 was using
the Winston log info's "level" attribute... which was tweaked by
colorize(). Winston log info objects have a Symbol.for("info")
property which has the unchanged level name:
https://github.com/winstonjs/winston#streams-objectmode-and-info-objects

This commit also changes (fix) what npm test runs in the
instrumentation-winston package. Before this, npm test was attempting
to test against winston@2 and winston@3 -- presumably for better
coverage. However, it ended up only ever testing with winston@2
(test-v1-v2 would install winston@2 and test, then test-v3 would
run the same test again with whatever current version is installed,
which is now winston@2).

The (IMO) correct answer here is:

• npm test tests against the latest ver of the target module (winston@3)
• npm run test-all-versions handles testing against other versions
• coverage can take a back seat. (Aside: changes coming as part of
  chore: improve test workflow and coverage reports #2866
  will, IIUC, provide coverage from test-all-versions runs.)

Closes: #2952

[trentm]

Before this, npm test was attempting
to test against winston@2 and winston@3 -- presumably for better
coverage.

Yup.
My changes here are undoing what was done in #2684

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main@215c2b5). Learn more about missing BASE report.
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

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Files with missing lines	Coverage Δ
packages/winston-transport/src/utils.ts	100.00% <100.00%> (ø)

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[hectorhdzg]

LGTM, thanks for taking care of this