Downgrade from Database 7.1 to 7.0

Configuration changes

Replace the flush-size namespace configuration parameter with an explicit write-block-size 8M. In Database 7.1 and higher the write-block-size was pinned to 8MiB. If you wish to reduce it, you will need to zeroize the drives on each downgraded node before restarting it. If you do not explicitly adjust the write-block-size correctly, it will implicitly be assigned a 1MiB value, which is smaller than the 8MiB storage. This will manifest in the following error on startup:
```
May 19 2024 17:26:14 GMT: INFO (drv_ssd): (drv_ssd.c:1056) /test/dev/xvdf has 5120 wblocks of size 1048576 May 19 2024 17:26:14 GMT: CRITICAL (drv_ssd): (drv_ssd.c:2390) /test/dev/xvdf: can't change write-block-size from 8388608 to 1048576
```
Replace your post-write-cache namespace configuration parameter with a post-write-queue. If you keep your write-block-size at 8MiB, you can divide the post-write-cache by 8MiB to get the number of write-blocks to cache.
Remove any configuration parameters added in Database 7.1 from your configuration file: default-password-file, indexes-memory-budget, evict-indexes-memory-pct, default-read-touch-ttl-pct, auto-revive, tls-refresh-period, batch-max-requests.