Updated otel linux requirements - removed Oracle 7

[maulikp-splunk]

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Describe the change

Updated otel linux requirements - removed Oracle 7 support for Linux since latest release dropped support for Oracle 7 - https://github.com/signalfx/splunk-otel-collector/releases/tag/v0.121.0

[aurbiztondo-splunk]

Thanks for the fix, @maulikp-splunk!

[aurbiztondo-splunk]

Heretto updated - eg https://help-staging.splunk.com/en/splunk-observability-cloud/get-data-in/get-data-into-splunk-observability-cloud/splunk-distribution-of-the-opentelemetry-collector/collector-for-linux/install-the-collector-for-linux-tools