Change logo to rainbow for June

[Oanh-and-only-Oanh]

Change Topcoder logo to rainbow for June 1st.

All Topcoder sites including our MFEs.
file:///Users/Oanh/Downloads/topcoder%20icon%20pride.svg

[dedywahyudi]

@Oanh-and-only-Oanh the svg not uploaded

[dedywahyudi]

@Oanh-and-only-Oanh @luizrrodrigues

This is ready:

PR: #5548

[luizrrodrigues]

@SathyaJayabal Deployed to QA env.

[SathyaJayabal]

verified on qa