[Remote Store] Add upload timestamp to metada file to be used in conflict resolution

[sachinpkale]

Is your feature request related to a problem? Please describe.

• Currently, we store metadata file in the remote store with: metadata__<Primary Term>__<Generation>__<UUID>.
• Primary term and generation are used to compare 2 metadata files and to get the latest one.
• But in some cases like primary - primary recovery, primary term and generation will be same.
• For this, we use UUID based comparison to have random but consistent way of resolving conflicts.
• As we are adding support for refresh level durability, it is important to get the latest uploaded metadata file.
• We can't just add timestamp in the filename as it will result in too many metadata files.
• The initial approach we are thinking of is to add timestamp info in the contents of metadata file.

[sachinpkale]

Moving to 2.7.0

[DarshitChanpura]

Hey @sachinpkale This issue will be marked for next-release v2.8.0 on (Apr 17) as that is the code-freeze date for v2.7.0. Please let me know if otherwise.

[DarshitChanpura]

Tagging it for next release: v2.8.0

[sachinpkale]

This is not required anymore