Use spread to handle variadic args of path.join

[willeastcott]

Changes this:

To this:

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[kungfooman]

Very nice, proper argument names help a lot. Currently RTI.js is generating a list of every one of them:

[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/path.js
[0] [0] generateTypeChecks> join> Missing param: section
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/string.js
[0] [0] generateTypeChecks> fromCodePoint> Missing param: args
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/tags.js
[0] [0] generateTypeChecks> Tags#add> Missing param: name
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/tags.js
[0] [0] generateTypeChecks> Tags#remove> Missing param: name
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/tags.js
[0] [0] generateTypeChecks> Tags#has> Missing param: query
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/scene/graph-node.js
[0] [0] generateTypeChecks> GraphNode#findByTag> Missing param: query
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/core/math/curve-set.js
[0] [0] generateTypeChecks> CurveSet#constructor> Missing param: curveKeys
[0] [0] [WARN] /var/www/html/playcanvas-engine-rti/src/framework/asset/asset-registry.js
[0] [0] generateTypeChecks> AssetRegistry#findByTag> Missing param: query

(first one you fixed here)

Should the others also be fixed?

[willeastcott]

The others do need fixing, yeah.