fix: correct spelling of `SpectraFit` #6253

Job	Run time
🧹 Pre-commit	1m 0s
🏗️ Build & Test Python 3.10 - macOS-latest - x64 - pull_request	1m 37s
🏗️ Build & Test Python 3.9 - macOS-latest - x64 - pull_request	1m 37s
🏗️ Build & Test Python 3.12 - macOS-latest - x64 - pull_request	3m 37s
🏗️ Build & Test Python 3.12 - ubuntu-latest - x64 - pull_request	4m 3s
🏗️ Build & Test Python 3.11 - ubuntu-latest - x64 - pull_request	3m 19s
🏗️ Build & Test Python 3.11 - macOS-latest - x64 - pull_request	3m 8s
🏗️ Build & Test Python 3.10 - ubuntu-latest - x64 - pull_request	3m 9s
🏗️ Build & Test Python 3.12 - windows-latest - x64 - pull_request	2m 58s
🏗️ Build & Test Python 3.9 - windows-latest - x64 - pull_request	1m 55s
🏗️ Build & Test Python 3.11 - windows-latest - x64 - pull_request	2m 29s
🏗️ Build & Test Python 3.10 - windows-latest - x64 - pull_request	2m 35s
🏗️ Build & Test Python 3.9 - ubuntu-latest - x64 - pull_request	2m 58s
📚 Build Documentation	7m 5s
🏗️ Install from Wheel	22s
🏗️ Minimal Build	43s
	42m 35s

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