Outdated versions of GRPC-Binary and GTM-session-fetcher

### Description

### Outdated versions of GRPC-Binary and GTM-session-fetcher

The latest version of Firebase (12.12.1 right now) has 2 outdated dependencies:

| Package | Current | Latest | URL |
|------|---------|---------------|-----|
| grpc-binary | 1.69.0 | 1.69.1 | https://github.com/google/grpc-binary.git |
| gtm-session-fetcher | 3.5.0 | 5.2.0 | https://github.com/google/gtm-session-fetcher.git |

Concern:
gtm-session-fetcher in particular is almost 2 years old: https://github.com/google/gtm-session-fetcher/releases

### Reproducing the issue

To reproduce:
- install Firebase SDK (iOS, via SPM, currently 12.12.1)
- run `swift outdated`, you get the table output above

### Firebase SDK Version

12.12.1

### Xcode Version

26.4

### Installation Method

Swift Package Manager

### Firebase Product(s)

All

### Targeted Platforms

iOS

### Relevant Log Output

```shell

```

### If using Swift Package Manager, the project's Package.resolved

Expand Package.resolved snippet

```json

Replace this line with the contents of your Package.resolved.

```

### If using CocoaPods, the project's Podfile.lock

_No response_