Makefile.am: fix shell typo [#2624] #283

Job	Run time
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, no, no)	4m 44s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, no, libusb-1.0)	4m 41s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, no, libusb-0.1)	4m 37s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, nss, no)	4m 31s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, nss, libusb-1.0)	4m 50s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, nss, libusb-0.1)	4m 43s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, openssl, no)	4m 42s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, openssl, libusb-1.0)	4m 59s
Analyze (cpp, ubuntu-latest, CC=gcc CXX=g++, openssl, libusb-0.1)	5m 9s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, no, no)	4m 43s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, no, libusb-1.0)	4m 31s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, no, libusb-0.1)	4m 27s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, nss, no)	6m 32s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, nss, libusb-1.0)	4m 38s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, nss, libusb-0.1)	4m 38s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, openssl, no)	4m 46s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, openssl, libusb-1.0)	4m 43s
Analyze (cpp, ubuntu-latest, CC=clang CXX=clang++, openssl, libusb-0.1)	4m 41s
Analyze (python, ubuntu-latest, PYTHON=python3, no, no)	1m 52s
	1h 28m 27s

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