The ornamental design for a gate latch, as shown and described.
FIG. 1 is a top perspective view of a gate latch showing my new design.
FIG. 2 is a bottom perspective view of a gate latch showing my new design.
FIG. 3 is a rear elevation view of a gate latch showing my new design.
FIG. 4 is a front elevation view of a gate latch showing my new design.
FIG. 5 is a top elevation view of a gate latch showing my new design.
FIG. 6 is a bottom elevation view of a gate latch showing my new design.
FIG. 7 is a first side elevation view of a gate latch showing my new design; and,
FIG. 8 is a second side elevation view of a gate latch showing my new design.
The broken lines, which define the bounds of the claimed design, form no part thereof. The broken lines environmental are for illustrative purposes only and form no part of the claimed design.