build: Update SVGO to latest v2.3.0 and re-optimize SVGs

SVGO v2.x changed configuration to JS, amending configuration.
Adding new 'minify-svg' npm script.
Also re-optimize SVGs.

Bug: T278656
Change-Id: I88ebed650be0d20b71bca6f15f3aa70b6b5eb42a

.svgo.config.js

@@ -0,0 +1,55 @@
+/**
+ * SVGO Configuration
+ * Recommended options from:
+ * https://www.mediawiki.org/wiki/Manual:Coding_conventions/SVG#Exemplified_safe_configuration
+ */
+const { extendDefaultPlugins } = require( 'svgo' );
+module.exports = {
+	multipass: true,
+	plugins: extendDefaultPlugins( [
+		{
+			name: 'cleanupIDs',
+			active: false
+		},
+		{
+			name: 'removeDesc',
+			active: false
+		},
+		{
+			name: 'removeRasterImages',
+			active: true
+		},
+		{
+			name: 'removeTitle',
+			active: false
+		},
+		{
+			name: 'removeViewBox',
+			active: false
+		},
+		{
+			// If the SVG doesn't start with an XML declaration, then its MIME type will
+			// be detected as "text/plain" rather than "image/svg+xml" by libmagic and,
+			// consequently, MediaWiki's CSSMin CSS minifier. libmagic's default database
+			// currently requires that SVGs contain an XML declaration:
+			// https://github.com/threatstack/libmagic/blob/master/magic/Magdir/sgml#L5
+			name: 'removeXMLProcInst',
+			active: false
+		},
+		{
+			name: 'sortAttrs',
+			active: true
+		}
+	] ),
+
+	// Configure the indent (default 4 spaces) used by `--pretty` here:
+	// @see https://github.com/svg/svgo/blob/master/lib/svgo/js2svg.js#L6 for more config options
+	//
+	// Unfortunately EOL cannot be configured, SVGO uses the platform's EOL marker.
+	// On non-unix systems the linebreaks will be normalized to LF (unix) only at git commit,
+	// assuming `core.autocrlf` is 'true' (default) or 'input'.
+	js2svg: {
+		indent: "\t",
+		pretty: true,
+	}
+}