Bump flat and mocha in /src/CSharpToTypeScript.VSCodeExtension#59

dependabot[bot] wants to merge 1 commit intomasterAdrianWilczynski/CSharpToTypeScript:masterfrom

dependabot/npm_and_yarn/src/CSharpToTypeScript.VSCodeExtension/flat-and-mocha-5.0.2AdrianWilczynski/CSharpToTypeScript:dependabot/npm_and_yarn/src/CSharpToTypeScript.VSCodeExtension/flat-and-mocha-5.0.2Copy head branch name to clipboard