check whether yurt manager's container is ready in e2e

[vie-serendipity]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:
/kind bug
/kind documentation
/kind enhancement
/kind good-first-issue
/kind feature
/kind question
/kind design
/sig ai
/sig iot
/sig network
/sig storage

What this PR does / why we need it:

Add check about the yurt manager container's readiness in e2e, otherwise the deployment webhook won't be ready at update of coredns.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

other Note

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In response to this:

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:
/kind bug
/kind documentation
/kind enhancement
/kind good-first-issue
/kind feature
/kind question
/kind design
/sig ai
/sig iot
/sig network
/sig storage

What this PR does / why we need it:

Add check about the yurt manager container's readiness in e2e, otherwise the deployment webhook won't be ready at update of coredns.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

other Note

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[codecov]

Codecov Report

Merging #1631 (426dd79) into master (4efa1bf) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1631   +/-   ##
=======================================
  Coverage   50.93%   50.93%           
=======================================
  Files         137      137           
  Lines       16029    16029           
=======================================
  Hits         8164     8164           
  Misses       7126     7126           
  Partials      739      739           

Flag	Coverage Δ
unittests	50.93% <ø> (ø)

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[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[openyurt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: rambohe-ch, vie-serendipity

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• OWNERS [rambohe-ch]

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[rambohe-ch]

/lgtm