gh-144702: Use standard terminology in class pattern error message #2208

Job	Run time
x86_64-pc-windows-msvc/msvc-free-threading	4m 29s
x86_64-apple-darwin/clang	24m 42s
x86_64-pc-windows-msvc/msvc	10m 10s
x86_64-unknown-linux-gnu/gcc	8m 58s
x86_64-unknown-linux-gnu/gcc-free-threading	8m 13s
aarch64-unknown-linux-gnu/gcc	7m 8s
aarch64-apple-darwin/clang	11m 20s
	1h 15m 0s

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