gh-129011: Update comments in FileIO to match current code #144497

Job	Run time
Change detection / Create context from changed files	17s
Ubuntu SSL tests with OpenSSL (ubuntu-24.04, 3.0.15)	4m 21s
Ubuntu SSL tests with OpenSSL (ubuntu-24.04, 3.1.7)	2m 36s
Check if Autoconf files are up to date	27s
Windows MSI${{ '' }}	0s
Ubuntu SSL tests with OpenSSL (ubuntu-24.04, 3.2.3)	3m 32s
Docs	0s
Ubuntu SSL tests with OpenSSL (ubuntu-24.04, 3.3.2)	2m 47s
Ubuntu SSL tests with OpenSSL (ubuntu-24.04, 3.4.0)	3m 56s
Check if generated files are up to date	5m 18s
Hypothesis tests on Ubuntu	8m 56s
Address sanitizer (ubuntu-24.04)	10m 30s
CIFuzz (address)	20m 0s
Cross build Linux	4m 19s
CIFuzz (undefined)	22m 46s
CIFuzz (memory)	21m 59s
WASI / build and test	4m 51s
Windows / build (arm64)	3m 16s
Windows (free-threading) / build (arm64)	3m 18s
Windows / build and test (Win32)	16m 55s
Windows / build and test (x64)	16m 5s
macOS (free-threading) / build and test (ghcr.io/cirruslabs/macos-runner:sonoma)	4m 8s
Windows (free-threading) / build and test (x64)	23m 48s
macOS / build and test (ghcr.io/cirruslabs/macos-runner:sonoma)	3m 34s
macOS / build and test (macos-13)	13m 59s
Ubuntu / build and test (ubuntu-24.04-arm)	10m 17s
Ubuntu / build and test (ubuntu-24.04)	8m 58s
Ubuntu (free-threading) / build and test (ubuntu-24.04)	12m 32s
Ubuntu (free-threading) / build and test (ubuntu-24.04-arm)	13m 23s
Ubuntu (bolt) / build and test (ubuntu-24.04)	13m 45s
Thread sanitizer / Thread sanitizer	5m 52s
Thread sanitizer (free-threading) / Thread sanitizer	8m 41s
All required checks pass	4s
	4h 35m 10s

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