Support https when return cog xml?Thank

[EthanLiangX]

<ServiceMetadataURL xlink:href="https://domain/cog/WMTSCapabilities.xml?tile_format=png&tile_scale=1&TileMatrixSetId=WebMercatorQuad&url=xxx&..."/>
</Capabilities>

[vincentsarago]

Dear @olongfen while we appreciate feedback on the project and new contribution please be aware that a title and 3lines of code isn't enough to explain an issue.