feat: bump Python OpenTelemetry SDK to 1.15

[kuisathaverat]

What does this PR do?

• Remove support for Python 3.6 and 3.7
• add support for Python 3.11
• Bump OpenTelemetry SDK to 1.15.0
• Update Elastic demo to 8.6.0

[apmmachine]

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• Start Time: 2023-01-18T11:40:15.662+0000

• Duration: 4 min 47 sec

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Test	Results
Failed	0
Passed	22
Skipped	0
Total	22

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