Fix marking gix-packetline-blocking copy auto-generated

In c957ab8 (#1340), I intended to mark the contents of
`gix-packetline-blocking/src` as auto-generated for
github-linguist, but I did not do so correctly, because giving the
directory as a path does not specify the `linguist-generated`
attribute as being unset for the contents.

This fixes that. The bug, and fix, is revealed by comparing the
output of `github-linguist --breakdown` before and after this:

	--- a   2024-11-18 15:45:57.376285107 -0500
	+++ b   2024-11-18 15:46:44.808328857 -0500
	@@ -1,6 +1,6 @@
	-94.14%  Rust
	-4.58%   Shell
	-1.19%   HTML
	+94.08%  Rust
	+4.63%   Shell
	+1.20%   HTML
	 0.09%   Makefile

	 Makefile:
	@@ -682,23 +682,6 @@
	 gix-pack/tests/pack/multi_index/mod.rs
	 gix-pack/tests/pack/multi_index/verify.rs
	 gix-pack/tests/pack/multi_index/write.rs
	-gix-packetline-blocking/src/decode.rs
	-gix-packetline-blocking/src/encode/async_io.rs
	-gix-packetline-blocking/src/encode/blocking_io.rs
	-gix-packetline-blocking/src/encode/mod.rs
	-gix-packetline-blocking/src/lib.rs
	-gix-packetline-blocking/src/line/async_io.rs
	-gix-packetline-blocking/src/line/blocking_io.rs
	-gix-packetline-blocking/src/line/mod.rs
	-gix-packetline-blocking/src/read/async_io.rs
	-gix-packetline-blocking/src/read/blocking_io.rs
	-gix-packetline-blocking/src/read/mod.rs
	-gix-packetline-blocking/src/read/sidebands/async_io.rs
	-gix-packetline-blocking/src/read/sidebands/blocking_io.rs
	-gix-packetline-blocking/src/read/sidebands/mod.rs
	-gix-packetline-blocking/src/write/async_io.rs
	-gix-packetline-blocking/src/write/blocking_io.rs
	-gix-packetline-blocking/src/write/mod.rs
	 gix-packetline/src/decode.rs
	 gix-packetline/src/encode/async_io.rs
	 gix-packetline/src/encode/blocking_io.rs

(The test was done on Ubuntu 18.04 LTS ESM with `github-linguist`
provided by the `ruby-github-linguist` package, version 5.3.3-1.)

In addition to fixing that, this also simplifies `.gitattributes`
files throughout the repository. This simplification includes
removing redundant `clrf=input` (discussed in #1676) and a
spurious unrecognized `-eof` (see #1689), changing lone `**` to `*`
where equivalent, and some other changes.

This also makes the style of `.gitattributes` files more consistent,
using `foo`/`-foo` rather than `foo=true`/`foo=false` everywhere
even where both work, and using whitespace more consistently.

.gitattributes

@@ -1,11 +1,11 @@
 **/generated-archives/*.tar* filter=lfs-disabled diff=lfs merge=lfs -text
 
 # assure line feeds don't interfere with our working copy hash
-*.sh text crlf=input eol=lf
-justfile text crlf=input eol=lf
+*.sh text eol=lf
+justfile text eol=lf
 
 # have GitHub include fixture-making scripts when it counts code
-**/tests/fixtures/**/*.sh linguist-vendored=false
+**/tests/fixtures/**/*.sh -linguist-vendored
 
 # have GitHub treat the gix-packetline-blocking src copy as auto-generated
-gix-packetline-blocking/src/ linguist-generated=true
+/gix-packetline-blocking/src/**/* linguist-generated

gix-config/tests/.gitattributes

@@ -1,4 +1 @@
-# assure line feeds don't interfere with our working copy hash 
-/fixtures/**/* text eol=lf
 /fixtures/repo-config.crlf text eol=crlf
-

gix-config/tests/fixtures/fuzzed/.gitattributes

@@ -1 +1 @@
-*.config -text -eof
+*.config -text

gix-object/tests/fixtures/.gitattributes

@@ -1,2 +1,2 @@
 # assure newlines aren't butchered as they matter for testing
-**/*.txt text crlf=input   eol=lf
+*.txt text eol=lf

gix-protocol/tests/fixtures/.gitattributes

@@ -1 +1 @@
-** -text
+* -text