switch to backticks for string interpolation

src/packages/conat/socket/server.ts

@@ -211,7 +211,7 @@ export class ConatSocketServer extends ConatSocketBase {
       try {
         await socket.end({ timeout });
       } catch (err) {
-        console.log("WARNING: error ending socket -- ${err}");
+        console.log(`WARNING: error ending socket -- ${err}`);
       }
     };
     await Promise.all(Object.keys(this.sockets).map(end));

src/packages/frontend/jupyter/nbgrader/clear-mark-regions.ts

@@ -31,7 +31,7 @@ function replace_mark_region(input: string): string | undefined {
       // check to make sure this isn't a nested BEGIN MARK SCHEME region
       if (in_region)
         throw Error(
-          "encountered nested ${begin_delimiter}, which is not allowed"
+          `encountered nested ${begin_delimiter}, which is not allowed`,
         );
 
       in_region = true;
@@ -52,7 +52,7 @@ function replace_mark_region(input: string): string | undefined {
   // we finished going through all the lines, but didn't find a
   // matching END statement
   if (in_region) {
-    throw Error("no matching ${end_delimiter} found");
+    throw Error(`no matching ${end_delimiter} found`);
   }
 
   // replace the area?

src/packages/server/conat/socketio/health.ts

@@ -14,7 +14,7 @@ export function handleHealth(
   res: ServerResponse,
 ) {
   const healthy = server.isHealthy();
-  logger.debug("/health reporting conat is healthy=${healthy}");
+  logger.debug(`/health reporting conat is healthy=${healthy}`);
   if (healthy) {
     res.statusCode = 200;
     res.end("healthy");