…start transparent for clients
## Describe your changes
Try to reestablish connection with pageserver if send is failed to be
able to make pageserver restart transparent for client
## Issue ticket number and link
https://github.com/neondatabase/neon/issues/1138
## Checklist before requesting a review
- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.
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Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
a34e78d084