Modify text in Korean top page for KubeCon announcement

[jihoon-seo]

This is a Bug Report

Problem:

Issue #23009: "Modify text in top page for KubeCon announcement"

KubeCon NA 2020 is now virtual

Proposed Solution:

In content/ko/_index.html

As-is:

        <a href="https://events.linuxfoundation.org/kubecon-cloudnativecon-europe/?utm_source=kubernetes.io&utm_medium=nav&utm_campaign=kccnceu20" button id="desktopKCButton">Attend KubeCon in Amsterdam on August 13-16, 2020</a>
        <br>
        <br>
        <br>
        <br>
        <a href="https://events.linuxfoundation.org/kubecon-cloudnativecon-europe/?utm_source=kubernetes.io&utm_medium=nav&utm_campaign=kccnceu20" button id="desktopKCButton">Attend KubeCon EU virtually on August 17-20, 2020</a>

To-be: (Make the same with content/en/_index.html)

        <a href="https://events.linuxfoundation.org/kubecon-cloudnativecon-europe/?utm_source=kubernetes.io&utm_medium=nav&utm_campaign=kccnceu20" button id="desktopKCButton">Attend KubeCon EU virtually on August 17-20, 2020</a>
        <br>
        <br>
        <br>
        <br>
        <a href="https://events.linuxfoundation.org/kubecon-cloudnativecon-north-america/?utm_source=kubernetes.io&utm_medium=nav&utm_campaign=kccncna20" button id="desktopKCButton">Attend KubeCon NA virtually on November 17-20, 2020</a>

Page to Update: https://kubernetes.io/ko/

[jihoon-seo]

/language ko

[seokho-son]

@jihoon-seo Could you help us fix this issue ? If you can, you can self assign this issue and open a PR to master branch. (FYI, Korean l10n team guide contributors to use Korean working branch, such as dev-1.18-ko.10, for general localization contributions. But, we accept bug fix PR to master branch to sync with EN changes.)

[jihoon-seo]

@seokho-son Sure! I will handle it.