Arnold Schwarzenegger continues to kick-start his career as an action hero after leaving politics and weathering an astonishing infidelity scandal. The former “Governator” signed to star yesterday in “Ten,” a movie about a DEA task force. The movie — by the writer of Bruce Willis’ “Die Hard” relaunch, “A Good Day to Die Hard,” Skip Woods — is the latest in a string of upcoming action projects for “Ahnuld,” opposite stars including Liam Hemsworth, Sylvester Stallone and 50 Cent. “Ten” will be directed by David Ayer, the “Training Day” writer who shot the Jake Gyllenhaal LAPD movie “End of Watch.” Upstart Open Road Films will distribute “Ten.”