Resolve banner through cms

[daylennguyen]

Gatsby-Image-Sharp does not play well with SVG files

7:40:19 PM: error GraphQL Error Field "banner" must not have a selection since type "String" has no subfields.
7:40:19 PM:   file: /opt/build/repo/src/templates/index-page.js
7:40:19 PM:    1 |
7:40:19 PM:    2 |   query IndexPageTemplate {
7:40:19 PM:    3 |     markdownRemark(frontmatter: { templateKey: { eq: "index-page" } }) {
7:40:19 PM:    4 |       frontmatter {
7:40:19 PM: >  5 |         banner {
7:40:19 PM:      |                ^
7:40:19 PM:    6 |           childImageSharp {
7:40:19 PM:    7 |             fixed(width: 860) {
7:40:19 PM:    8 |               ...GatsbyImageSharpFixed_withWebp_tracedSVG
7:40:19 PM:    9 |             }
7:40:19 PM:   10 |           }
7:40:19 PM:   11 |         }
7:40:19 PM:   12 |         termtitle
7:40:19 PM:   13 |         termtext
7:40:19 PM:   14 |         intro {
7:40:19 PM:   15 |           heading

Will likely direct import to resolve.