Updated version handing code in application. Small fixes.

src/components/Footer.jsx

@@ -1,6 +1,6 @@
 import React from "react";
 import { Box, Typography, Container, Link, Grid } from "@mui/material";
-import { VERSION } from "../version";
+import { IS_RELEASE, VERSION } from "../version";
 
 function Footer() {
   return (
@@ -19,7 +19,7 @@ function Footer() {
           <Grid size={{ xs: 12, md: 6 }}>
             <Typography variant="body2" color="text.secondary">
               <strong>JMESPath Testing Tool</strong>{" "}
-              {VERSION === "unknown" ? VERSION : `v${VERSION}`} - Created for
+              {IS_RELEASE ? VERSION : `${VERSION}-dev`} - Created for
               testing and validating JMESPath expressions
             </Typography>
           </Grid>

src/components/MainPage.jsx

@@ -214,7 +214,6 @@ function MainPage({
 
       <Paper
         sx={{
-          mb: 1,
           flexShrink: 0,
           bgcolor: "background.paper",
           border: 1,