Make sed pattern for SYS_PIP portable across macOS and Linux (#4163)

- Updated sed pattern in Makefile.vars to use [0-9][0-9]* for Python version matching.
- Ensures correct detection of pip executable for all supported Python versions on both GNU and BSD sed.

Author: agl29

Makefile.vars

@@ -77,7 +77,7 @@ BLD_DIR_BIN := $(BLD_DIR_ENV)/bin
 # Sets up per-version BLD_DIR_ENV and INST_DIR_ENV variables.
 # Introduces version-specific requirement file generation via generate_requirements.py.
 SYS_PYTHON := $(shell IFS=:; for p in $$PATH; do if [ -x "$$p/$(PYTHON_VER)" ]; then echo "$$p/$(PYTHON_VER)"; break; fi; done)
-SYS_PIP := $(shell echo $(SYS_PYTHON) | sed "s/python\([0-9]\+\.[0-9]\+\)$$/pip\1/")
+SYS_PIP := $(shell echo $(SYS_PYTHON) | sed "s/python\([0-9][0-9]*\.[0-9][0-9]*\)$$/pip\1/")
 ENV_PYTHON := $(shell echo $(BLD_DIR_BIN)/$(shell basename $(SYS_PYTHON)))
 ENV_PIP := $(shell echo $(BLD_DIR_BIN)/$(shell basename $(SYS_PIP)))
 PYTHON_INCLUDE_DIR := $(shell $(SYS_PYTHON) -c "import sysconfig; print(sysconfig.get_path('include'))" 2>/dev/null)

desktop/core/generate_requirements.py

@@ -200,6 +200,7 @@ def __init__(self):
       "ppc64le": self.ppc64le_requirements,
       "x86_64": self.x86_64_requirements,
       "aarch64": self.aarch64_requirements,
+      "arm64": self.aarch64_requirements,  # arm64 is treated as aarch64
     }
     self.arch = platform.machine()
     self.python_version_string = f"{sys.version_info.major}.{sys.version_info.minor}"