📖 book: add videos from KubeCon and Let's chat about sessions

[sbueringer]

Signed-off-by: Stefan Büringer [email protected]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

[sbueringer]

/cherry-pick release-1.1

[k8s-infra-cherrypick-robot]

@sbueringer: once the present PR merges, I will cherry-pick it on top of release-1.1 in a new PR and assign it to you.

In response to this:

/cherry-pick release-1.1

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.

[tobiasgiese]

thanks 🙂 👍🏻

/lgtm

[fabriziopandini]

Thanks for adding those links!
/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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• OWNERS [fabriziopandini]

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[k8s-infra-cherrypick-robot]

@sbueringer: #6587 failed to apply on top of branch "release-1.1":

Applying: book: add videos from KubeCon and Let's chat about sessions
.git/rebase-apply/patch:36: trailing whitespace.
contributors and users of the Cluster API project. For more details and an up-to-date list of recordings of past sessions please 
warning: 1 line adds whitespace errors.
Using index info to reconstruct a base tree...
M	docs/book/src/developer/guide.md
Falling back to patching base and 3-way merge...
Auto-merging docs/book/src/developer/guide.md
CONFLICT (content): Merge conflict in docs/book/src/developer/guide.md
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 book: add videos from KubeCon and Let's chat about sessions
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherry-pick release-1.1

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.