Remove Scipy config file in LQ (#775)

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------------------------------------------------------------------------------------------------------------

**Context:**
Remove the required scipy config file used for the shots-based
measurement processes in LQ. The support is now maintained by passing
`SCIPY_LIBS_PATH` to the compiler.

**Description of the Change:**
Use `add_compile_definitions` to pass the variable to the compiler
instead of hardcoding it in `config.h`.

**Benefits:**
- Remove `config.h` from LQ distro package
- No need to run `git restore config.h` before each commit

**Possible Drawbacks:**

**Related GitHub Issues:**

---------

Co-authored-by: ringo-but-quantum <[email protected]>

.github/CHANGELOG.md

@@ -91,6 +91,9 @@
 * Remove the daily schedule from the "Compat Check w/PL - release/release" GitHub action.
   [(#746)](https://github.com/PennyLaneAI/pennylane-lightning/pull/746)
 
+* Remove the required `scipy` config file for LightningQubit. The support is now maintained by passing `SCIPY_LIBS_PATH` to the compiler.
+  [(#775)](https://github.com/PennyLaneAI/pennylane-lightning/pull/775)
+
 ### Documentation
 
 * Add installation instructions and documentation for `lightning.tensor`.

.gitignore

@@ -31,7 +31,6 @@ doc/code/api/
 kokkos/
 PennyLane_Lightning_Kokkos.egg-info/
 PennyLane_Lightning.egg-info/
-pennylane_lightning/core/src/utils/config.h
 prototypes/
 tests/__pycache__/
-venv/
+venv/

CMakeLists.txt

@@ -106,8 +106,7 @@ if(ENABLE_LAPACK)
         message(FATAL_ERROR "Unsupported platform: ${CMAKE_SYSTEM_NAME}")
     endif()
 
-    configure_file(${CMAKE_CURRENT_SOURCE_DIR}/pennylane_lightning/core/src/utils/config.h.in
-        ${CMAKE_CURRENT_SOURCE_DIR}/pennylane_lightning/core/src/utils/config.h)
+    add_compile_definitions(SCIPY_LIBS_PATH="${SCIPYLIBS}")
 
     message(STATUS "Python scipy-lib path: ${SCIPYLIBS}")
 endif()

pennylane_lightning/core/_version.py

@@ -16,4 +16,4 @@
    Version number (major.minor.patch[-label])
 """
 
-__version__ = "0.37.0-dev47"
+__version__ = "0.37.0-dev48"

pennylane_lightning/core/src/utils/UtilLinearAlg.hpp

@@ -32,8 +32,6 @@
 
 #include "SharedLibLoader.hpp"
 
-#include "config.h"
-
 /// @cond DEV
 namespace {
 // Declare heev function pointers to access corresponding functions in