OPERA PGE Release 2 Release Candidate 2.1

Release Candidate 2.1 for the R2 OPERA PGEs. This release includes updated point releases of both the L2_CSLC_S1 and L2_RTC_S1 PGEs, targeting the recent CalVal point releases of the corresponding SAS. This release also updates the following:

• Implements the latest changes to the naming conventions for both the baseline and static layer products
• Updates the ISO XML metadata to be in sync with the currently available product metadata.
• Container build script updates to support Oracle Linux 8 as the base SAS image OS.

What's Changed

• RTC-S1 CalVal v4.1 PGE Integration by @collinss-jpl in #334
• CSLC-S1 CalVal v5.1 PGE Integration by @collinss-jpl in #336

Full Changelog: 2.0.0-rc.2.0...2.0.0-rc.2.1