docs: fix comment typos in BufferReflow, Types, and addons (addons only)

Co-authored-by: Daniel Imms <Tyriar@users.noreply.github.com>

addons/addon-serialize/test/SerializeAddon.test.ts

@@ -192,7 +192,7 @@ test.describe('SerializeAddon', () => {
     const cols = 10;
     const line = '+'.repeat(cols);
     const lines: string[] = [
-      sgr(FG_P16_GREEN) + line,  // Workaround: If we clear all flags a the end, serialize will use \x1b[0m to clear instead of the sepcific disable sequence
+      sgr(FG_P16_GREEN) + line,  // Workaround: If we clear all flags at the end, serialize will use \x1b[0m to clear instead of the specific disable sequence
       sgr(INVERSE) + line,
       sgr(BOLD) + line,
       sgr(UNDERLINED) + line,

addons/addon-webgl/src/WebglRenderer.ts

@@ -664,7 +664,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this.dimensions.device.canvas.height = this._terminal.rows * this.dimensions.device.cell.height;
     this.dimensions.device.canvas.width = this._terminal.cols * this.dimensions.device.cell.width;
 
-    // The the size of the canvas on the page. It's important that this rounds to nearest integer
+    // The size of the canvas on the page. It's important that this rounds to nearest integer
     // and not ceils as browsers often have floating point precision issues where
     // `window.devicePixelRatio` ends up being something like `1.100000023841858` for example, when
     // it's actually 1.1. Ceiling may cause blurriness as the backing canvas image is 1 pixel too