Fix docker action branch (#1346)

**Context:**
Currently the docker build action always uses the dockerfile from the
master branch, regardless of which lightning branch we are testing. When
the dockerfile is updated in master, this can cause failure when testing
stable docker builds.

**Description of the Change:**
Update docker action to use dockerfile from the same lightning branch as
that being tested.

**Benefits:**
Stable docker build works

**Possible Drawbacks:**

**Related GitHub Issues:**


[latest docker
build](https://github.com/PennyLaneAI/pennylane-lightning/actions/runs/22314096215)
[stable docker
build](https://github.com/PennyLaneAI/pennylane-lightning/actions/runs/22314110578)

[sc-112280]

---------

Co-authored-by: ringo-but-quantum <github-ringo-but-quantum@xanadu.ai>
Co-authored-by: Ali Asadi <10773383+maliasadi@users.noreply.github.com>

Author: 3 people

.github/CHANGELOG.md

@@ -32,6 +32,9 @@
 
 <h3>Internal changes ⚙️</h3>
 
+- Updated Github docker build action to use relevant lightning branch.
+  [(#1346)](https://github.com/PennyLaneAI/pennylane-lightning/pull/1346)
+
 - Remove dependency for GCC-11 when building `lightning.amdgpu`.
   [(#1343)](https://github.com/PennyLaneAI/pennylane-lightning/pull/1343)
 

.github/workflows/docker_linux_x86_64.yml

@@ -52,6 +52,8 @@ jobs:
 
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.lightning-version }}
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3

pennylane_lightning/core/_version.py

@@ -16,4 +16,4 @@
 Version number (major.minor.patch[-label])
 """
 
-__version__ = "0.45.0-dev19"
+__version__ = "0.45.0-dev20"