[parser] enh: allow whitespace in Format specification #8483

Job	Run time
Build LFortran to WASM and Upload	17m 56s
Check SciPy Build and Test Run	17m 55s
LFortran CI (3.10, windows-2019)	22m 2s
Check Out-of-Source Debug build	1m 27s
LFortran CI (3.10, macos-latest)	8m 21s
Check Debug build	2m 40s
Test integration_tests with GFortran	39s
LFortran CI (3.10, ubuntu-latest)	8m 8s
Check Release build	2m 23s
Test C/C++ backend	2m 1s
Test Fortran backend	1m 58s
Test CPP	6m 2s
Test LLVM 10	2m 33s
Test LLVM->WASM 10	6m 51s
Test LLVM 14	2m 27s
Test LLVM->WASM 16	6m 39s
Test WASM	1m 42s
Test without LLVM Backend	4m 32s
Test LLVM 15	2m 33s
Check Third Party Code Compilation	7m 16s
Test LLVM 16	2m 35s
Documentation	4m 28s
Upload Tarball	1m 51s
	2h 14m 59s

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