Stir together black beans, corn, green bell pepper, red bell pepper, cheese, green onions, and taco seasonings in a large bowl and give it a nice mix. Spoon about 2 tablespoon mixture in center of each egg roll wrapper. Fold the top corner of the wrapper over filling, tucking the tip of corner under filling; fold left and right corners overfilling. Lightly brush remaining corner with water tightly roll filled end toward the remaining corner, and gently press to seal.