If you're looking to enhance your svg, consider using this modified version created in Inkscape. Converting bitmap images to svg can lead to pixelation issues, as evident in your current design. Take advantage of Inkscape's capabilities to import the bitmap icon and refine it through manual drawing.
For animation purposes, give this code a try to achieve the desired effect. Make sure to note the single closed path that has been created for this svg.
<svg viewBox="0 0 256 256">
<path class="path" d="m 15.625507,46.199537 55.767886,-32.030352 55.623047,32.281229 -0.14485,64.311586 0.14485,-64.311586 55.76788,-32.030352 55.62305,32.281229 -0.14485,64.311579 -55.76788,32.03036 -55.62305,-32.28123 55.62305,32.28123 -0.14485,64.31158 -55.76788,32.03035 L 70.958866,207.10393 71.103708,142.79235 126.87159,110.762 71.103708,142.79235 15.480664,110.51112 Z" style="fill:#fff;stroke:#000;stroke-width:13;stroke-linejoin:round;stroke-linecap:round" />
</svg>
.path {
stroke-linejoin:round;
stroke-linecap:round;
stroke-dasharray: 1500;
stroke-dashoffset: 1500;
animation: dash 5s linear alternate infinite;
}
@keyframes dash {
from {
stroke-dashoffset: 1500;
}
to {
stroke-dashoffset: 0;
}
}
<!DOCTYPE html>
<html lang="en" >
<head>
<meta charset="UTF-8">
<title>CodePen - Basic Example of SVG Line Drawing, Backward and Forward</title>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/normalize/5.0.0/normalize.min.css">
<link rel="stylesheet" href="./style.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/prefixfree/1.0.7/prefixfree.min.js"></script>
</head>
<body>
<svg viewBox="0 0 256 256">
<path class="path" fill="#fff" stroke="#000000" stroke-width="13" d="m 15.625507,46.199537 55.767886,-32.030352 55.623047,32.281229 -0.14485,64.311586 0.14485,-64.311586 55.76788,-32.030352 55.62305,32.281229 -0.14485,64.311579 -55.76788,32.03036 -55.62305,-32.28123 55.62305,32.28123 -0.14485,64.31158 -55.76788,32.03035 L 70.958866,207.10393 71.103708,142.79235 126.87159,110.762 71.103708,142.79235 15.480664,110.51112 Z"/>
</svg>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js'></script>
</body>
</html>