In cockroachdb#68918 we reverted
a change that taught stream ingestion processors to wait for a cutover
on losing connection to the client. This was the first part of introducing
the concept of generations to c2c streaming. The change was reverted due
to a leaked goroutine during stress testing.

This change does not alter any of the core logic but simply makes the test
more reliable by adding a `Streaming` testing knob. This allows us to intercept
when the stream ingestion processor receives an Event and perform the necessaery
testing.

Release justification: non-production code changes. Revert a revert
of previously checked in logic by fixing the testing infrastructure
that was leaking the goroutine.

69262: streamingccl: unrevert graceful cutover of stream ingestion r=pbardea a=adityamaru

In #68918 we reverted
a change that taught stream ingestion processors to wait for a cutover
on losing connection to the client. This was the first part of introducing
the concept of generations to c2c streaming. The change was reverted due
to a leaked goroutine during stress testing.

This change does not alter any of the core logic but simply makes the test
more reliable by adding a `Streaming` testing knob. This allows us to intercept
when the stream ingestion processor receives an Event and perform the necessary
testing.

Fixes: #68701
Fixes: #68795

Release justification (non-production code changes): Revert a revert
of previously checked in logic by fixing the testing infrastructure
that was leaking the goroutine.

69470: sql: Fix SHOW ZONE CONFIGURATIONS with very long constraints r=arulajmani a=ajstorm

Previously, in the presence of very long constraints fields, SHOW ZONE
CONFIGURATIONS would output the constraints with `\n` characters mixed in. This
was due to the fact that the yaml.v2 library contained an 80 character line
limit. We recently pulled in some commits to our fork of the yaml library which
allows the line length to be configurable. With that change, we can now
configure the line length to be unlimited in the case where we're showing the
zone configuration, and get around the ugliness of the `\n` characters.

Release note (sql change): Fixes a bug in SHOW ZONE CONFIGURATIONS where long
constraints fields may show `\n` characters.

Release justification: Low risk change to existing functionality.

Co-authored-by: Anne Zhu <anne.zhu@cockroachlabs.com>
Co-authored-by: Adam Storm <storm@cockroachlabs.com>