Bump actions/cache from 4 to 5

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/elixir.yml

@@ -37,7 +37,7 @@ jobs:
           elixir-version: '1.19'
           otp-version: '28'
       - name: Restore dependencies cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: deps
           key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
@@ -60,7 +60,7 @@ jobs:
           elixir-version: '1.19'
           otp-version: '28'
       - name: Restore dependencies cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: deps
           key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
@@ -80,7 +80,7 @@ jobs:
           elixir-version: '1.19'
           otp-version: '28'
       - name: Restore dependencies cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: deps
           key: ${{ runner.os }}-mix-${{ hashFiles('**/mix.lock') }}
@@ -90,7 +90,7 @@ jobs:
       # Don't cache PLTs based on mix.lock hash, as Dialyzer can incrementally update even old ones
       # Cache key based on Elixir & Erlang version (also useful when running in matrix)
       - name: Restore PLT cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         id: plt_cache
         with:
           key: |