refactor(core): ensure compatibility with typescript strict flag (#30993)

As part of FW-1265, the `@angular/core` package is made compatible
with the TypeScript `--strict` flag. This already unveiled a few bugs,
so the strictness flag seems to help with increasing the overall code health.

Read more about the strict flag [here](https://www.typescriptlang.org/docs/handbook/compiler-options.html)

PR Close #30993

packages/core/src/render3/styling/host_instructions_queue.ts

@@ -61,7 +61,7 @@ function findNextInsertionIndex(buffer: HostInstructionsQueue, priority: number)
  * Iterates through the host instructions queue (if present within the provided
  * context) and executes each queued instruction entry.
  */
-export function flushQueue(context: StylingContext): void {
+export function flushQueue(this: unknown, context: StylingContext): void {
   const buffer = context[StylingIndex.HostInstructionsQueue];
   if (buffer) {
     for (let i = HostInstructionsQueueIndex.ValuesStartPosition; i < buffer.length;