build(deps): Bump github.com/creachadair/tomledit from 0.0.16 to 0.0.18 (#8392)

Bumps [github.com/creachadair/tomledit](https://github.com/creachadair/tomledit) from 0.0.16 to 0.0.18.
<details>
<summary>Commits</summary>
<ul>
<li><a href="5802e262c6"><code>5802e26</code></a> Release v0.0.18</li>
<li><a href="3c9daf1a4a"><code>3c9daf1</code></a> document that we don't validate</li>
<li><a href="da8c938af4"><code>da8c938</code></a> Remove non-applicable test cases.</li>
<li><a href="ac4210b0d1"><code>ac4210b</code></a> parser: ensure unclosed arrays are not treated as empty</li>
<li><a href="f98f82fec1"><code>f98f82f</code></a> parser: ensure array separators are present</li>
<li><a href="ea1671ecca"><code>ea1671e</code></a> scanner: clean up some issues in escape and space handling</li>
<li><a href="8168589a25"><code>8168589</code></a> scanner: filter bad commas in numeric literals</li>
<li><a href="83189e20b7"><code>83189e2</code></a> scanner: fix some issues in multiline string recognition</li>
<li><a href="bdc8e22990"><code>bdc8e22</code></a> scanner: allow space separators in date-time strings</li>
<li><a href="1ab2c8d654"><code>1ab2c8d</code></a> Add compliance tests.</li>
<li>Additional commits viewable in <a href="https://github.com/creachadair/tomledit/compare/v0.0.16...v0.0.18">compare view</a></li>
</ul>
</details>
<br />


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</details>

go.mod

@@ -75,7 +75,7 @@ require (
 	github.com/charithe/durationcheck v0.0.9 // indirect
 	github.com/chavacava/garif v0.0.0-20210405164556-e8a0a408d6af // indirect
 	github.com/containerd/continuity v0.2.1 // indirect
-	github.com/creachadair/tomledit v0.0.16
+	github.com/creachadair/tomledit v0.0.18
 	github.com/daixiang0/gci v0.3.3 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/denis-tingaikin/go-header v0.4.3 // indirect

go.sum

@@ -229,8 +229,8 @@ github.com/creachadair/atomicfile v0.2.5 h1:wkOlpsjyJOvJ3Hd8juHKdirJnCSIPacvtY21
 github.com/creachadair/atomicfile v0.2.5/go.mod h1:BRq8Une6ckFneYXZQ+kO7p1ZZP3I2fzVzf28JxrIkBc=
 github.com/creachadair/taskgroup v0.3.2 h1:zlfutDS+5XG40AOxcHDSThxKzns8Tnr9jnr6VqkYlkM=
 github.com/creachadair/taskgroup v0.3.2/go.mod h1:wieWwecHVzsidg2CsUnFinW1faVN4+kq+TDlRJQ0Wbk=
-github.com/creachadair/tomledit v0.0.16 h1:PDNxgDjeeiNk1cyFfliIVQmagh1jPbDMabOw9yfSKLk=
-github.com/creachadair/tomledit v0.0.16/go.mod h1:gvtfnSZLa+YNQD28vaPq0Nk12bRxEhmUdBzAWn+EGF4=
+github.com/creachadair/tomledit v0.0.18 h1:gleeCnEgMPYcaBz5KN/1CN9yycF5n6Q2py7Ahu6yc7A=
+github.com/creachadair/tomledit v0.0.18/go.mod h1:gvtfnSZLa+YNQD28vaPq0Nk12bRxEhmUdBzAWn+EGF4=
 github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7DoTY=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/cyphar/filepath-securejoin v0.2.2/go.mod h1:FpkQEhXnPnOthhzymB7CGsFk2G9VLXONKD9G7QGMM+4=